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RE: [gt750uk] MPG

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  • Gary Cobb
    I dont get any surging on mine anyway mate, but a good point. To: gt750uk@yahoogroups.co.ukFrom: keith_rudd@btinternet.comDate: Tue, 30 Sep 2008 21:55:03
    Message 1 of 27 , Oct 1, 2008
    • 0 Attachment
      I dont get any surging on mine anyway mate, but a good point.




      To: gt750uk@...
      From: keith_rudd@...
      Date: Tue, 30 Sep 2008 21:55:03 +0000
      Subject: Re: [gt750uk] MPG

      Seems low speed tickover ... about 1000rpm ...... reduces effects of "surging" on the overrun!!!!
      Come on Tim get him told!!!!!!

      ----- Original Message ----
      From: Gary Cobb <cobb.trans@hotmail. co.uk>
      To: gt750uk@yahoogroups .co.uk
      Sent: Tuesday, 30 September, 2008 10:52:28 PM
      Subject: RE: [gt750uk] MPG

      Why? All of us down here run about the same consumption and tickover. Nothings ever gone wrong with them




       



      To: gt750uk@yahoogroups .co.uk
      From: keith_rudd@btintern et.com
      Date: Tue, 30 Sep 2008 21:45:41 +0000
      Subject: Re: [gt750uk] MPG


      Ooooo Cobby, I think Tim will have something to say about that LOLLLLLLLLLLLLL! !!!!

      ----- Original Message ----
      From: Gary Cobb <cobb.trans@hotmail. co.uk>
      To: gt750uk@yahoogroups .co.uk
      Sent: Tuesday, 30 September, 2008 10:43:32 PM
      Subject: RE: [gt750uk] MPG

      Mine gives about 105 to 120 before turning onto reserve (depending on how i ride). When i had my original kettle new they dealer reckoned 1200 rpm is the correct tickover setting, i`ve just stuck with that! 




      To: gt750uk@yahoogroups .co.uk
      From: mark.reeves@ ntlworld. com
      Date: Tue, 30 Sep 2008 22:01:59 +0100
      Subject: Re: [gt750uk] MPG

      
      mind you saying that, my engine is spot on, and it dont like tick over at 1000 rpm, sounds more comfortable at 11000 - 12000
      ----- Original Message -----
      Sent: Tuesday, September 30, 2008 9:42 PM
      Subject: Re: [gt750uk] MPG

      Could be a little hard to start from cold or having stood for a while ..... tickover minimum 1200rpm or stall!!!!! And I was going to try a change of carbs!!! 
       

       

      ----- Original Message ----
      From: mark reeves <mark.reeves@ ntlworld. com>
      To: gt750uk@yahoogroups .co.uk
      Sent: Tuesday, 30 September, 2008 9:38:11 PM
      Subject: Re: [gt750uk] MPG

      

      was it difficult to start ! did it tick over OK !!! LLOL
      ----- Original Message -----
      Sent: Tuesday, September 30, 2008 9:35 PM
      Subject: Re: [gt750uk] MPG

      That's what I thought ...... standard rings in a 0.05 over bore!!!! The other ring gaps were well past serviceable but no where near as much!!! Oh ...and yes the feeler gauges are metric!!!!!!

      ----- Original Message ----
      From: mark reeves <mark.reeves@ ntlworld. com>
      To: gt750uk@yahoogroups .co.uk
      Sent: Tuesday, 30 September, 2008 9:31:53 PM
      Subject: Re: [gt750uk] MPG

      

      I have never seen a ring gap that big Keith, did it have the correct sized rings in !
      ----- Original Message -----
      Sent: Tuesday, September 30, 2008 9:28 PM
      Subject: Re: [gt750uk] MPG

      Nope!!!! Had to hold back a fleet of busses that were waiting to drive through the gap!!!! LOLLLLLLLLLLLLLLL

      ----- Original Message ----
      From: mark reeves <mark.reeves@ ntlworld. com>
      To: gt750uk@yahoogroups .co.uk
      Sent: Tuesday, 30 September, 2008 9:24:49 PM
      Subject: Re: [gt750uk] MPG

      

      1.25mm are you JOKING !
      ----- Original Message -----
      Sent: Tuesday, September 30, 2008 9:16 PM
      Subject: Re: [gt750uk] MPG

      MPG does of course very much depend on the condition of your engine, it's state of tune or wear, drive chain, choice of sprockets, wheel bearings, brakes not binding and right wrist!!!! Even a thicker viscocity oil will cause additional drag and require more fuel to churn the gearbox ..... maybe not much but some. On my red B model Kettle I always, get 99 miles between fill ups and reserve which equates to what .... I dunno, never ever did MPG comparisons on any of my cars/bikes, just fill em up when they need it. Took the barrels off the red Kettle a couple of weeks ago and found huge ring gaps, 1.25mm in one instance, so it's a rebore from 0.5 to 0.10 for me!!!!
       
      My blue A model Kettle MPG seems to get more miles to a tankfull, but I haven't ridden it from full to reserve, my mate who rode it to the Haze just filled up when I did and put less £'s worth of petrol in!!!!  
       
      Keith
        

      ----- Original Message ----
      From: David Fortune <david@kilvinton23. fsnet.co. uk>
      To: gt750uk@yahoogroups .co.uk
      Sent: Tuesday, 30 September, 2008 8:39:07 PM
      Subject: [gt750uk] MPG

      Hi Guys
      Does anybody ever bother working out their fuel consumption? I seem to
      be filling up too regularly. 13.35 litres only lasted 66 miles which
      equates to 24 mpg. I do not go that crazy, do you think I am set up
      okay? Standard pipes, standard carbs, electonic ignition.
      Interested to know what others achieve.
      Cheers
      David











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    • Gary Cobb
      ask Tim Dave, he`s the man i normally ask if i cant suss it To: gt750uk@yahoogroups.co.ukFrom: david@kilvinton23.fsnet.co.ukDate: Wed, 1 Oct 2008 05:49:25
      Message 2 of 27 , Oct 1, 2008
      • 0 Attachment
        ask Tim Dave, he`s the man i normally ask if i cant suss it




        To: gt750uk@...
        From: david@...
        Date: Wed, 1 Oct 2008 05:49:25 +0000
        Subject: [gt750uk] Re: MPG

        --- In gt750uk@yahoogroups .co.uk, "David Fortune" <david@...> wrote:
        >
        >Thanks for all the replies; seems, as I thought, that I am a little on
        the low side. It seems to run okay, what should I be checking?
        David




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      • Ace Venturi
        Hi Guys, sorry to be so late in on this one...so here comes some lengthy bed-time reading ...... :o)))) Now this sounds all too familiar! I had very similar
        Message 3 of 27 , Oct 1, 2008
        • 0 Attachment
          Hi Guys, sorry to be so late in on this one...so here comes some
          lengthy bed-time reading ...... :o))))

          Now this sounds all too familiar! I had very similar issues with my
          B - about 85-95 miles before reserve, sometimes less, but never much
          more - equating to mid-late 20's in mpg at best.

          I spent a long time trying various things out on several sets of
          carbs without any marked improvement, until I changed the (looked
          OK) needle jets and needles for NOS (expensive!), and hey presto!! I
          was am now getting a good 38-45 mpg on "normal" main road runs, up
          to 49-50 mpg when we went to Holland (mainly cruising about 55-65
          mph) and down into the mid-late 30's on motorways at steady 70-80
          mph two-up. I now usually expect at least 120 miles (sometimes
          140+) before reserve, dependant on riding style/conditions.

          The major difference it makes is that you regain a lot of the lower
          end torque/smoothness and get rid of the 4-stroking/stuttering on
          part-throttle/cruise, so you don't need to keep the revs up all the
          time to get a smooth run.

          If you think about the way the CV carb works, most (probably 80%) of
          the running we do will be on the needle jets - you can mess about
          all you like with mains and pilots, but if your needle jets are worn
          and letting too much mixture through mid-range, it will mess up the
          mid-range running where most of us would ride - Binky excepted :o))

          If the needle jets aren't right, it will often run better further up
          the rev range, so I used to ride at 3000-4500 rpm on cruising to
          keep it smooth. But if you get it right, you can run around at 1500-
          3000 rpm all day - buckets of torque and dead smooth.

          By being able to keep the revs down but still ride well, it makes a
          BIG BIG difference to the range/fuel consumption.

          Obviously, everything else needs to be set up properly. And don't
          forget that if you have a spacer between the fuel tap and tank (some
          models had them, others didn't - I'll leave that to the marque
          specialists to fight over!), you will get longer before reserve but
          less on reserve. BTW I have a spacer on my B fuel tap.

          Now on tickovers and "hunting on the over-run":-

          If your pilot system is good and well set up, according to Suzuki,
          you should be aiming at a tickover of 1000 rpm. The main issue we
          see is a poor tickover for whatever reason, to which the instant
          answer is to up the throttle stop screw, leaving the butterflies
          slightly open and the hunting will manifest itself as the throttle
          valves never fully shut. If you can get a steady tickover at 1200
          and it doesn't hunt, I'd leave alone - i.e. if it ain't broke don't
          fix it.

          However, when I'm confronted (all too frequently) with complaints of
          hunting, the 1st question I ask is what's the tickover set to ... if
          above about 1150 to 1200, it indicates the pilot system is faulty or
          not set up properly, the latter is more common and you can almost
          always get hunting.

          Quite often though, it is simply down to poor balance and this can
          be cured by rebalancing well, but sometimes, the problem lies in
          sorting the pilots out.

          The best way to set it up is to get the t/o steady, trim the air
          screws to smooth it as much as possible, drop it back down a bit
          more, repeat the trimming, and repeat trim and thottle stop out
          until you have a tickover as close to 1000 rpm (or below if
          possible) as you can get. This should minimise any hunting if not
          eliminate it.

          If you want to prove the point, back the throttle stop out until it
          won't tickover - if the surging goes away or reduces significantly,
          then your problem is the pilot setup. If it makes little or no
          difference, you have another problem (e.g. poor balance or blocked
          pilot jets).

          Also, it appears that some carb sets have pilot air jets that are
          worn or damaged to the extent that you can get a low tickover (or
          not) but you still get "hunting" on the over-run, or in severe
          cases, "surging" on part throttle/cruise (this is where I make the
          distinction between "hunting" and "surging").

          Suzuki US released a tech bulletin in the 70's covering fixing this
          with screw-in reduction pilot air jets. These seem to have dried up
          from Suzuki now and were getting ridiculously expensive (around £10
          each or more) anyway, but I have recently managed to source them
          direct from Mikuni at a more reasonable price (£15 a set of 3).

          I am not convinced that this is a "cure all" but seems to help in
          certain cases. I would still currently consider this as a "last
          resort" fix but reserve the right to change my mind later as it is
          still an ongoing project. The mod only means tapping the hole for
          the pilot air jet with an M4 bottoming tap and screwing the
          reduction air jet in, so it is reversible if it doen't work. I know
          some have tried it to no avail, and some swear it is the best fix
          they have done, so it isn't a cure-for-all, but can help.

          New member Shane Woods is currently working on fettling his hunting
          A model with reduction pilot air jets - on 0.8's at present (good),
          about to try 0.7's to see if that gets them even better, so let's
          wait and see how he gets on. I know Tom B (Norway) has also
          previously reported well on the reduction pilot air jets, but I have
          experienced and heard of mixed results on other sets.

          Now I must get on and sort my own tickover out again - I had it
          working beautifully before Holland but it has since gone off again,
          so I have to back it off at present to a point where it won't hold
          tickover and then just hold it on the throttle at lights to avoid
          hunting. Mid-range it is fabulous and rolls on and off the throttle
          without a hint of stuttering, surging or 4/8-stroking and I can ride
          it normally at 1500-3000 rpm all day with that fabulous turbo-like
          boost when the power kicks in around 3500-4000 rpm. Just how I
          remember my nearly new A Model Kettle back in the 70's!!!!.
          Beautiful to ride once again.

          Hope this is of some small help, let me know your thoughts guys 'n
          gals.... please don't take this info as definitive as we are all
          learning all of the time, but the more knowledge we share, the
          sooner we'll all be happy Kettle fettlers!!!!.

          "Ace"

          --- In gt750uk@..., Gary Cobb <cobb.trans@...> wrote:
          >
          > ask Tim Dave, he`s the man i normally ask if i cant suss it
          >
          > To: gt750uk@...: david@...: Wed, 1 Oct 2008 05:49:25 +0000Subject:
          [gt750uk] Re: MPG
          >
          >
          >
          >
          > --- In gt750uk@..., "David Fortune" <david@>
          wrote:>>Thanks for all the replies; seems, as I thought, that I am a
          little on the low side. It seems to run okay, what should I be
          checking?David
          >
          >
          >
          >
          >
          > _________________________________________________________________
          > Get all your favourite content with the slick new MSN Toolbar -
          FREE
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        • mark reeves
          Tim, I remember debating with you ( at the Blue Haze several years ago ) over these so called cheap carb kits that contained the cheap needles ( Keyster), and
          Message 4 of 27 , Oct 1, 2008
          • 0 Attachment
            Tim, I remember debating with you ( at the Blue Haze several years ago ) over these so called cheap carb kits that contained the cheap needles ( Keyster), and you seemed totally sold on them.
             
            I have always held the opinion that these kits are totally crap, especially the needles and jets, as the cliché go's :- you get what you pay for !
             
            I'm amazed why people don't just bite the bullet and buy genuine carb parts , as these after market kits really are pants !
             
            Mark
             
             
            ----- Original Message -----
            Sent: Wednesday, October 01, 2008 6:49 PM
            Subject: [gt750uk] Re: MPG

            Hi Guys, sorry to be so late in on this one...so here comes some
            lengthy bed-time reading ...... :o))))

            Now this sounds all too familiar! I had very similar issues with my
            B - about 85-95 miles before reserve, sometimes less, but never much
            more - equating to mid-late 20's in mpg at best.

            I spent a long time trying various things out on several sets of
            carbs without any marked improvement, until I changed the (looked
            OK) needle jets and needles for NOS (expensive!) , and hey presto!! I
            was am now getting a good 38-45 mpg on "normal" main road runs, up
            to 49-50 mpg when we went to Holland (mainly cruising about 55-65
            mph) and down into the mid-late 30's on motorways at steady 70-80
            mph two-up. I now usually expect at least 120 miles (sometimes
            140+) before reserve, dependant on riding style/conditions.

            The major difference it makes is that you regain a lot of the lower
            end torque/smoothness and get rid of the 4-stroking/stutteri ng on
            part-throttle/ cruise, so you don't need to keep the revs up all the
            time to get a smooth run.

            If you think about the way the CV carb works, most (probably 80%) of
            the running we do will be on the needle jets - you can mess about
            all you like with mains and pilots, but if your needle jets are worn
            and letting too much mixture through mid-range, it will mess up the
            mid-range running where most of us would ride - Binky excepted :o))

            If the needle jets aren't right, it will often run better further up
            the rev range, so I used to ride at 3000-4500 rpm on cruising to
            keep it smooth. But if you get it right, you can run around at 1500-
            3000 rpm all day - buckets of torque and dead smooth.

            By being able to keep the revs down but still ride well, it makes a
            BIG BIG difference to the range/fuel consumption.

            Obviously, everything else needs to be set up properly. And don't
            forget that if you have a spacer between the fuel tap and tank (some
            models had them, others didn't - I'll leave that to the marque
            specialists to fight over!), you will get longer before reserve but
            less on reserve. BTW I have a spacer on my B fuel tap.

            Now on tickovers and "hunting on the over-run":-

            If your pilot system is good and well set up, according to Suzuki,
            you should be aiming at a tickover of 1000 rpm. The main issue we
            see is a poor tickover for whatever reason, to which the instant
            answer is to up the throttle stop screw, leaving the butterflies
            slightly open and the hunting will manifest itself as the throttle
            valves never fully shut. If you can get a steady tickover at 1200
            and it doesn't hunt, I'd leave alone - i.e. if it ain't broke don't
            fix it.

            However, when I'm confronted (all too frequently) with complaints of
            hunting, the 1st question I ask is what's the tickover set to ... if
            above about 1150 to 1200, it indicates the pilot system is faulty or
            not set up properly, the latter is more common and you can almost
            always get hunting.

            Quite often though, it is simply down to poor balance and this can
            be cured by rebalancing well, but sometimes, the problem lies in
            sorting the pilots out.

            The best way to set it up is to get the t/o steady, trim the air
            screws to smooth it as much as possible, drop it back down a bit
            more, repeat the trimming, and repeat trim and thottle stop out
            until you have a tickover as close to 1000 rpm (or below if
            possible) as you can get. This should minimise any hunting if not
            eliminate it.

            If you want to prove the point, back the throttle stop out until it
            won't tickover - if the surging goes away or reduces significantly,
            then your problem is the pilot setup. If it makes little or no
            difference, you have another problem (e.g. poor balance or blocked
            pilot jets).

            Also, it appears that some carb sets have pilot air jets that are
            worn or damaged to the extent that you can get a low tickover (or
            not) but you still get "hunting" on the over-run, or in severe
            cases, "surging" on part throttle/cruise (this is where I make the
            distinction between "hunting" and "surging").

            Suzuki US released a tech bulletin in the 70's covering fixing this
            with screw-in reduction pilot air jets. These seem to have dried up
            from Suzuki now and were getting ridiculously expensive (around £10
            each or more) anyway, but I have recently managed to source them
            direct from Mikuni at a more reasonable price (£15 a set of 3).

            I am not convinced that this is a "cure all" but seems to help in
            certain cases. I would still currently consider this as a "last
            resort" fix but reserve the right to change my mind later as it is
            still an ongoing project. The mod only means tapping the hole for
            the pilot air jet with an M4 bottoming tap and screwing the
            reduction air jet in, so it is reversible if it doen't work. I know
            some have tried it to no avail, and some swear it is the best fix
            they have done, so it isn't a cure-for-all, but can help.

            New member Shane Woods is currently working on fettling his hunting
            A model with reduction pilot air jets - on 0.8's at present (good),
            about to try 0.7's to see if that gets them even better, so let's
            wait and see how he gets on. I know Tom B (Norway) has also
            previously reported well on the reduction pilot air jets, but I have
            experienced and heard of mixed results on other sets.

            Now I must get on and sort my own tickover out again - I had it
            working beautifully before Holland but it has since gone off again,
            so I have to back it off at present to a point where it won't hold
            tickover and then just hold it on the throttle at lights to avoid
            hunting. Mid-range it is fabulous and rolls on and off the throttle
            without a hint of stuttering, surging or 4/8-stroking and I can ride
            it normally at 1500-3000 rpm all day with that fabulous turbo-like
            boost when the power kicks in around 3500-4000 rpm. Just how I
            remember my nearly new A Model Kettle back in the 70's!!!!.
            Beautiful to ride once again.

            Hope this is of some small help, let me know your thoughts guys 'n
            gals.... please don't take this info as definitive as we are all
            learning all of the time, but the more knowledge we share, the
            sooner we'll all be happy Kettle fettlers!!!! .

            "Ace"

            --- In gt750uk@yahoogroups .co.uk, Gary Cobb <cobb.trans@ ...> wrote:
            >
            > ask Tim Dave, he`s the man i normally ask if i cant suss it
            >
            > To: gt750uk@...: david@...: Wed, 1 Oct 2008 05:49:25 +0000Subject:
            [gt750uk] Re: MPG
            >
            >
            >
            >
            > --- In gt750uk@yahoogroups .co.uk, "David Fortune" <david@>
            wrote:>>Thanks for all the replies; seems, as I thought, that I am a
            little on the low side. It seems to run okay, what should I be
            checking?David
            >
            >
            >
            >
            >
            > ____________ _________ _________ _________ _________ _________ _
            > Get all your favourite content with the slick new MSN Toolbar -
            FREE
            > http://clk.atdmt. com/UKM/go/ 111354027/ direct/01/
            >

          • Ace Venturi
            Hi Mark, The Haze some years ago ???? I m not THAT old, am I??? :o)))) Early Keyster kits (in the old red/blue packaging) were definitely dubious, to say the
            Message 5 of 27 , Oct 1, 2008
            • 0 Attachment
              Hi Mark,

              The Haze "some years ago"???? I'm not THAT old, am I??? :o))))

              Early Keyster kits (in the old red/blue packaging) were definitely
              dubious, to say the least! - float bowl gaskets that don't fit
              without trimming, dodgy needles, main jets some reported as bad,
              sometimes the float valves didn't even fit......

              But newer kits (Red/White/Blue packaging) are generally much better,
              albeit not perfect. Certainly, I have tried recent Keyster needles
              against NOS Mikuni and they appear pretty much the same, if not
              slightly better with worn Needle jets.

              However, the REAL point is the cost and availability of NOS
              Suzuki/Mikuni parts.

              The float valves in the Keyster kits are very useable (with some
              care), the choke valve gaskets are long gone from Suzuki's parts
              list but ARE included in the Keyster kit.

              And NOS parts are getting harder and harder to get - it took Martin
              Crooks some 7-8 weeks to get me the 15 needle jets and needles I
              needed for my stock for jobs waiting! These bits are getting harder
              to source and going up in price all the time. And you know how
              resourceful Martin is?

              And Mikuni only ever supplied the BS-40 Z-0 needle jets as a "Suzuki-
              only" part, so no chance of futher supply once they're gone without
              re-manufacture. I know Andy at NRP has had a go at getting these re-
              made last year but was not happy with the quality and rejected them.

              A whole Keyster kit will cost you about £15 RRP (for each carb) or
              less?? - NOS float valves alone from Suzuki were (last time I
              looked) £27+ each plus VAT. I got some 2.5mm (Suzuki are 2.3mm but
              not available from Mikuni any more) float needle valves from Mikuni
              @ £23 +VAT and that INCLUDES my 20% discount!!. Float bowl gaskets
              ~£5, needles £9-10 each. Need I say more???

              If someone needs a float valve and a single gasket - immediately
              Keyster is cheapest route and can be made to work. Whether you want
              to use the other bits in the kit is totally optional.

              I've sourced lots of other bits - copper washers for float bowl
              drain, needle valve and choke valve, various O-rings, seals etc from
              the UK at good prices and can get more. I've also managed to source
              the butterfly spindle seals from Mikuni but they are F##ng expensive
              at £30/set, and I need to order in batches of 50 with a 2-3 month
              lead but at least we have a working stock in the UK for when they
              are needed.

              I've also just managed to source those elusive breather tube clips -
              Genuine Mikuni, but they took 10 weeks to get here and about £2.50
              each (got 24 in at present).

              Point is, if we all work at it, we can source more and more bits by
              being resourceful and building credible links with our only genuine
              Mikuni spares supplier in the UK (which I am constantly working on
              and making good progress), or keep paying increasingly inflated
              prices from dealers who recognise the value of the little stock they
              have left.

              Chris has helped re-manufacture various detail parts which were
              never available from Suzuki - some of the bits he has done have
              helped me make up a replacement bronze-lined rose joint kit for the
              RH carb oil pump link to replace the 'orrible little nylon/brass
              jobby originally fitted. That last one is out on a few bikes now
              and so far, they're all looking very good !!

              I am sure we will need your (and other club members) help in making
              more ofthese detail (but essential) bits up, so we need to talk
              further.

              We need to work with resourceful and skilled peeps like yourself,
              Martin, Reiner, Andy at NRP, Allens, etc. and our other suppliers to
              make sure that we secure these alternative supply routes and get the
              best deal for TKC club members available, so the rip-off merchants
              can't step in and fleece us genuine GT fans.

              A lot of NOS Suzuki stuff is drying up now and even the "best"
              dealers are hiking their prices on what they've got left.

              So there is some method in my madness - we have to make the best of
              a bad job in some cases, but getting these bikes running as they
              should is just such a pleasure to behold !! And with a bit of
              skill, is easily acheivable.

              As Andy McDowell ('er with the airbrushed out crinkles) says - "it's
              because your worth it"
              (noticed that we don't get any bust shots anymore?)
              :o)) O.O

              Cheers Pal

              "Ace"

              --- In gt750uk@..., "mark reeves" <mark.reeves@...>
              wrote:
              >
              > Tim, I remember debating with you ( at the Blue Haze several years
              ago ) over these so called cheap carb kits that contained the cheap
              needles ( Keyster), and you seemed totally sold on them.
              >
              > I have always held the opinion that these kits are totally crap,
              especially the needles and jets, as the cliché go's :- you get what
              you pay for !
              >
              > I'm amazed why people don't just bite the bullet and buy genuine
              carb parts , as these after market kits really are pants !
              >
              > Mark
              >
              >
              > ----- Original Message -----
              > From: Ace Venturi
              > To: gt750uk@...
              > Sent: Wednesday, October 01, 2008 6:49 PM
              > Subject: [gt750uk] Re: MPG
              >
              >
              > Hi Guys, sorry to be so late in on this one...so here comes some
              > lengthy bed-time reading ...... :o))))
              >
              > Now this sounds all too familiar! I had very similar issues with
              my
              > B - about 85-95 miles before reserve, sometimes less, but never
              much
              > more - equating to mid-late 20's in mpg at best.
              >
              > I spent a long time trying various things out on several sets of
              > carbs without any marked improvement, until I changed the
              (looked
              > OK) needle jets and needles for NOS (expensive!), and hey
              presto!! I
              > was am now getting a good 38-45 mpg on "normal" main road runs,
              up
              > to 49-50 mpg when we went to Holland (mainly cruising about 55-
              65
              > mph) and down into the mid-late 30's on motorways at steady 70-
              80
              > mph two-up. I now usually expect at least 120 miles (sometimes
              > 140+) before reserve, dependant on riding style/conditions.
              >
              > The major difference it makes is that you regain a lot of the
              lower
              > end torque/smoothness and get rid of the 4-stroking/stuttering
              on
              > part-throttle/cruise, so you don't need to keep the revs up all
              the
              > time to get a smooth run.
              >
              > If you think about the way the CV carb works, most (probably
              80%) of
              > the running we do will be on the needle jets - you can mess
              about
              > all you like with mains and pilots, but if your needle jets are
              worn
              > and letting too much mixture through mid-range, it will mess up
              the
              > mid-range running where most of us would ride - Binky
              excepted :o))
              >
              > If the needle jets aren't right, it will often run better
              further up
              > the rev range, so I used to ride at 3000-4500 rpm on cruising to
              > keep it smooth. But if you get it right, you can run around at
              1500-
              > 3000 rpm all day - buckets of torque and dead smooth.
              >
              > By being able to keep the revs down but still ride well, it
              makes a
              > BIG BIG difference to the range/fuel consumption.
              >
              > Obviously, everything else needs to be set up properly. And
              don't
              > forget that if you have a spacer between the fuel tap and tank
              (some
              > models had them, others didn't - I'll leave that to the marque
              > specialists to fight over!), you will get longer before reserve
              but
              > less on reserve. BTW I have a spacer on my B fuel tap.
              >
              > Now on tickovers and "hunting on the over-run":-
              >
              > If your pilot system is good and well set up, according to
              Suzuki,
              > you should be aiming at a tickover of 1000 rpm. The main issue
              we
              > see is a poor tickover for whatever reason, to which the instant
              > answer is to up the throttle stop screw, leaving the butterflies
              > slightly open and the hunting will manifest itself as the
              throttle
              > valves never fully shut. If you can get a steady tickover at
              1200
              > and it doesn't hunt, I'd leave alone - i.e. if it ain't broke
              don't
              > fix it.
              >
              > However, when I'm confronted (all too frequently) with
              complaints of
              > hunting, the 1st question I ask is what's the tickover set
              to ... if
              > above about 1150 to 1200, it indicates the pilot system is
              faulty or
              > not set up properly, the latter is more common and you can
              almost
              > always get hunting.
              >
              > Quite often though, it is simply down to poor balance and this
              can
              > be cured by rebalancing well, but sometimes, the problem lies in
              > sorting the pilots out.
              >
              > The best way to set it up is to get the t/o steady, trim the air
              > screws to smooth it as much as possible, drop it back down a bit
              > more, repeat the trimming, and repeat trim and thottle stop out
              > until you have a tickover as close to 1000 rpm (or below if
              > possible) as you can get. This should minimise any hunting if
              not
              > eliminate it.
              >
              > If you want to prove the point, back the throttle stop out until
              it
              > won't tickover - if the surging goes away or reduces
              significantly,
              > then your problem is the pilot setup. If it makes little or no
              > difference, you have another problem (e.g. poor balance or
              blocked
              > pilot jets).
              >
              > Also, it appears that some carb sets have pilot air jets that
              are
              > worn or damaged to the extent that you can get a low tickover
              (or
              > not) but you still get "hunting" on the over-run, or in severe
              > cases, "surging" on part throttle/cruise (this is where I make
              the
              > distinction between "hunting" and "surging").
              >
              > Suzuki US released a tech bulletin in the 70's covering fixing
              this
              > with screw-in reduction pilot air jets. These seem to have dried
              up
              > from Suzuki now and were getting ridiculously expensive (around
              £10
              > each or more) anyway, but I have recently managed to source them
              > direct from Mikuni at a more reasonable price (£15 a set of 3).
              >
              > I am not convinced that this is a "cure all" but seems to help
              in
              > certain cases. I would still currently consider this as a "last
              > resort" fix but reserve the right to change my mind later as it
              is
              > still an ongoing project. The mod only means tapping the hole
              for
              > the pilot air jet with an M4 bottoming tap and screwing the
              > reduction air jet in, so it is reversible if it doen't work. I
              know
              > some have tried it to no avail, and some swear it is the best
              fix
              > they have done, so it isn't a cure-for-all, but can help.
              >
              > New member Shane Woods is currently working on fettling his
              hunting
              > A model with reduction pilot air jets - on 0.8's at present
              (good),
              > about to try 0.7's to see if that gets them even better, so
              let's
              > wait and see how he gets on. I know Tom B (Norway) has also
              > previously reported well on the reduction pilot air jets, but I
              have
              > experienced and heard of mixed results on other sets.
              >
              > Now I must get on and sort my own tickover out again - I had it
              > working beautifully before Holland but it has since gone off
              again,
              > so I have to back it off at present to a point where it won't
              hold
              > tickover and then just hold it on the throttle at lights to
              avoid
              > hunting. Mid-range it is fabulous and rolls on and off the
              throttle
              > without a hint of stuttering, surging or 4/8-stroking and I can
              ride
              > it normally at 1500-3000 rpm all day with that fabulous turbo-
              like
              > boost when the power kicks in around 3500-4000 rpm. Just how I
              > remember my nearly new A Model Kettle back in the 70's!!!!.
              > Beautiful to ride once again.
              >
              > Hope this is of some small help, let me know your thoughts
              guys 'n
              > gals.... please don't take this info as definitive as we are all
              > learning all of the time, but the more knowledge we share, the
              > sooner we'll all be happy Kettle fettlers!!!!.
              >
              > "Ace"
              >
              > --- In gt750uk@..., Gary Cobb <cobb.trans@> wrote:
              > >
              > > ask Tim Dave, he`s the man i normally ask if i cant suss it
              > >
              > > To: gt750uk@: david@: Wed, 1 Oct 2008 05:49:25 +0000Subject:
              > [gt750uk] Re: MPG
              > >
              > >
              > >
              > >
              > > --- In gt750uk@..., "David Fortune" <david@>
              > wrote:>>Thanks for all the replies; seems, as I thought, that I
              am a
              > little on the low side. It seems to run okay, what should I be
              > checking?David
              > >
              > >
              > >
              > >
              > >
              > > __________________________________________________________
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              >
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