GT750 Carb Boot Issue - Help Please
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- Yeah Man, the Interstate
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GT750 Carb Boot Issue - Help Please
My carb boot doesn't seem to fit at all and I'm getting air coming thru where the boot does not fit onto the carb. This must affect the performance, right?
The boot is sitting up against the airbox ok. However, none of the three oulets fits fully onto the carb throats. I can get the top of each to sit on and push the bottoms into place - but they slide back (no matter how tight I do the band up) and do not seal onto the carb.
I've checked a mate's J model and his boot slides right up to the notches on the carbs and sit tight (as I'd expect).
What do you think is going on here? Ive tried loosening and sliding the carb back from the manifold to get more grip but this doesn't work either.
Is it possible the boot is the wrong one? It feels soft and pliable so I can't imagine it has shrunk that much. What else could it be off?
Thanks, Mike
The boot is sitting up against the airbox ok. However, none of the three oulets fits fully onto the carb throats. I can get the top of each to sit on and push the bottoms into place - but they slide back (no matter how tight I do the band up) and do not seal onto the carb.
I've checked a mate's J model and his boot slides right up to the notches on the carbs and sit tight (as I'd expect).
What do you think is going on here? Ive tried loosening and sliding the carb back from the manifold to get more grip but this doesn't work either.
Is it possible the boot is the wrong one? It feels soft and pliable so I can't imagine it has shrunk that much. What else could it be off?
Thanks, Mike
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Re: GT750 Carb Boot Issue - Help Please
Mike its possible the boot has shrunk but if its still soft it cant be that far off. The clamps you are using might be bottoming out before they actually hold the boot secure enough to the carb bellmouths so see if you can locate some other ones that wont touch together on their screw flanges so easily.
I'd get the boot up to the carbs by slackening the airbox from above, then securing the three clamps where they should be and then re-bolting the box afterwards.
I'd get the boot up to the carbs by slackening the airbox from above, then securing the three clamps where they should be and then re-bolting the box afterwards.
Two strokes, its just that simple.
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Re: GT750 Carb Boot Issue - Help Please
i found most sucess by taking the left and right carbs off, then using a foot long piece of wood behind the boot against the frame to hold the boot all the way on, then tighten up the clamp then the same process with the outer carbs.
but it gets easier with repetition.
cheers mark
but it gets easier with repetition.
cheers mark
She will never be pretty but hoping she will be a fun ride.
1973 SUZUKI GT750K.=SOLD
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Re: GT750 Carb Boot Issue - Help Please
Thanks guys, I shall investigate further. Impressed with the speed of reply! Will let you know how things turn out.
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Re: GT750 Carb Boot Issue - Help Please
One of the problems with molded rubber parts is if they are fitted badly they will take a 'set' and then you have to force them back into their original shape.
In a case such as yours Mike, I'll bet if you look at the rear portion below the boot to airbox joint its wall might be bulging backwards a bit form being like that for a while.
Heat from the engine only makes this condition worse over time as well so it probably needs help to reshape it, let us know how you get on with it.
In a case such as yours Mike, I'll bet if you look at the rear portion below the boot to airbox joint its wall might be bulging backwards a bit form being like that for a while.
Heat from the engine only makes this condition worse over time as well so it probably needs help to reshape it, let us know how you get on with it.
Two strokes, its just that simple.
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Re: GT750 Carb Boot Issue - Help Please
Performance wise, air entering there shouldn't hurt a thing. If the air leak was on the engine side, then yes. ---- endless fits.
I was born with nothing and still have most of it left.
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Re: GT750 Carb Boot Issue - Help Please
Any updates on the issue Mike????
Two strokes, its just that simple.
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Re: GT750 Carb Boot Issue - Help Please
Hi Allan,
Thanks for thinking of my bike and following up on this. I haven't actually been near the old girl for a week or so - which may be leaving her feeling somewhat neglected and unloved No, I tell a lie, I did actually polish the pipes and was impressed with the chrome on closer inspection!
I've been busy organising a bike show in my city for pre-1985 Japanese bikes. It's all set to go for this weekend and we have 84 bikes registered: ranging from barnfinds through to overly loved garage dwellers. The majority are ridden regularly however. Looks as though Suzuki is going to be the biggest group, with a few Buffalos and several Katanas as well. We lost a few entries due to the darn earthquake - and the pesky ongoing aftershocks (which have only just settled after 5 weeks ). I'll post a few pics after the show - last years was won by a beautiful Suzuki Cobra.
Once this is over, I shall attack the carb boot and get back to you. Thanks again for your interest.
Mike
Thanks for thinking of my bike and following up on this. I haven't actually been near the old girl for a week or so - which may be leaving her feeling somewhat neglected and unloved No, I tell a lie, I did actually polish the pipes and was impressed with the chrome on closer inspection!
I've been busy organising a bike show in my city for pre-1985 Japanese bikes. It's all set to go for this weekend and we have 84 bikes registered: ranging from barnfinds through to overly loved garage dwellers. The majority are ridden regularly however. Looks as though Suzuki is going to be the biggest group, with a few Buffalos and several Katanas as well. We lost a few entries due to the darn earthquake - and the pesky ongoing aftershocks (which have only just settled after 5 weeks ). I'll post a few pics after the show - last years was won by a beautiful Suzuki Cobra.
Once this is over, I shall attack the carb boot and get back to you. Thanks again for your interest.
Mike
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Re: GT750 Carb Boot Issue - Help Please
I've finally gotten around to doing something with the new toy. Here are some shots of the offending carb boot. No matter what I try, she won't sit onto the carbs properly. The top part of each circular boot fits but the bottom part slides off - even if I tighten the bands up as far as they will go. The inside of the boot has two complete tubes coming into the boot whilst the centre on is cut/ripped off.
Does this look like the correct boot? If so how come (despite lots of patient persuasion ) it won't sit on correctly.
Thanks for any further thoughts.
Mike
Does this look like the correct boot? If so how come (despite lots of patient persuasion ) it won't sit on correctly.
Thanks for any further thoughts.
Mike
Burt Munro + John Britten + Kim Newcombe + Ivan Mauger = Kiwi Street Cred
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Re: GT750 Carb Boot Issue - Help Please
I had the same problem on my T350, it seems like the rubber has "shrinked" slightly so it won't fit propperly any more. I had some sucsess with heating the boot with boiling water making it more fleexible but wouldn't stay on for long so in the end I switched to KN filters instead.
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Re: GT750 Carb Boot Issue - Help Please
i dont know if they are still available new from suzuki?.
maybe a new one would fit correctly.
but if in doubt K&N.
maybe a new one would fit correctly.
but if in doubt K&N.
She will never be pretty but hoping she will be a fun ride.
1973 SUZUKI GT750K.=SOLD
yamaha speedtwinn 100 barn find =SOLD
1x 1973 kawasaki H1 (restored)
1x 1973 kawasaki H1 (basket case) =SOLD
1982 HONDA CB900F =SOLD
1982 YAMAHA RD350LC.
1985 RZ350N
1973 SUZUKI GT750K.=SOLD
yamaha speedtwinn 100 barn find =SOLD
1x 1973 kawasaki H1 (restored)
1x 1973 kawasaki H1 (basket case) =SOLD
1982 HONDA CB900F =SOLD
1982 YAMAHA RD350LC.
1985 RZ350N
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Re: GT750 Carb Boot Issue - Help Please
Mike thats not looking too good, its got some issues with it for sure now its off for viewing. 13880-31001 is the part number for the boot but it looks like a NLA item. You could search on ebay for one and hope its soft and pliable when you get it.
For now and in a pinch you can carefully drill two holes in the top metal plate in the upper cover just rearwards of the ones there now and tap them to M6 x1.00. This will move the whole airbox forwards just enough so it can reach the bellmouths with that boot.
For now and in a pinch you can carefully drill two holes in the top metal plate in the upper cover just rearwards of the ones there now and tap them to M6 x1.00. This will move the whole airbox forwards just enough so it can reach the bellmouths with that boot.
Two strokes, its just that simple.
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Re: GT750 Carb Boot Issue - Help Please
Thanks for that Allan, a nice practical interim option. I shall begin the hunting process for a replacement. In the meantime I'm going to clean and check the carbs. The task after that will be to address the petcock that isn't shutting off - lost the vacuum aspect. I am impressed with the acceleration, even in it's untuned state.
Thanks again, Mike
Thanks again, Mike
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Re: GT750 Carb Boot Issue - Help Please
Mike.
Take a tape measure, and measure from the inside of the main air intake to the front edge of the middle carb inlet, and let me know that dimension. I will compare that to a boot that I know is a good fit, and then the mistery should be solved as to the shrinkage factor. It's worth a shot. Cheers.
Fred
Take a tape measure, and measure from the inside of the main air intake to the front edge of the middle carb inlet, and let me know that dimension. I will compare that to a boot that I know is a good fit, and then the mistery should be solved as to the shrinkage factor. It's worth a shot. Cheers.
Fred
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Re: GT750 Carb Boot Issue - Help Please
Hey Fred,
Just been out to the mancave with a measuring stick. The distance you mentioned is 4.5 inches or around 11.5cm.
Thanks, Mike
Just been out to the mancave with a measuring stick. The distance you mentioned is 4.5 inches or around 11.5cm.
Thanks, Mike
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