re-installing GT750 carbs (or trying to).

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J Backlund
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re-installing GT750 carbs (or trying to).

Post by J Backlund »

Greetings! I'm putting my 1974 GT750 back together, but am stumped on getting the carb assembly back onto the cylinder head intake boots. It seems to be an almost impossible task unless there's a little secret to it. I've been trying to warm the rubber manifolds up with a hair dryer to make them more compliant, and smearing a little WD-40 onto them to lube them up but even with all that, it seems that the boots are too small for the carb outlets and still cannot wrestle those dang carbs back on.

What's the trick to this frustrating situation? More lube goo? more patience and sheer muscle? more heat?

:?
Thanks for any help in this matter.

(I posted this here before I saw the repair forum, apologies if this topic doesn't belong here)
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Re: re-installing GT750 carbs (or trying to).

Post by Suzsmokeyallan »

First off, if the boots are very hard you will need new ones as having an air leak on the intake side of the carbs will ruin your day and engine. They are quite pliable when new but with heat and age can become like rock and useless. You should be able to squeeze the ends inwards by your hand without too much effort if the are in usable condition.
One method I use to get the carbs on is to rest them on the engine then straddle the bike while its on the centre stand.
Next lift them up at each end and place the top portion of the rubbers just onto the cylinder intakes then as you push forwards tilt them downwards onto the cylinder intakes. Using grease helps as does WD40 and other types of lubes.
Two strokes, its just that simple.

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Re: re-installing GT750 carbs (or trying to).

Post by pearljam724 »

Like Allan said, you have to replace them. An oem set is hard to find under 120-150 bucks. This seller sells an aftermarket set for $40. An absolute bargain. Comes with new clamps also. Very quick shipper. I've purchased them and they are spot on replicas. http://www.ebay.com/itm/74-77-Suzuki-GT ... 25793566a2" onclick="window.open(this.href);return false;
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Re: re-installing GT750 carbs (or trying to).

Post by Cliff »

Try putting the rubber intakes on the carbs first, leave all the clamps loose, then install the assembly to the block. A little liquid dish soap on the rubbers makes everything slide together a lot easier!!
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Re: re-installing GT750 carbs (or trying to).

Post by oldjapanesebikes »

And what I have resorted to on occasion is a ratchet tie down strap and a piece of wood - loop the strap around the cylinder block and the carbs with the bit of wood across the mouth of the carbs, bit of lube on the boots and then ratchet away till they pop in. But note the comments above about the boots - if they are rock hard they are scrap. 8)
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Re: re-installing GT750 carbs (or trying to).

Post by J Backlund »

Thank you all very much, I will get a new set of boots before proceeding any further. I'll report back how it goes. Again, thanks!

Thanks for the link pearljam724, the boots are on their way to sunny South Dakota.
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Re: re-installing GT750 carbs (or trying to).

Post by pearljam724 »

Many gentleman on this site have helped me along the way. Just trying to return those favors.
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Re: re-installing GT750 carbs (or trying to).

Post by J Backlund »

I might get this old thing back on the road this spring yet...
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Re: re-installing GT750 carbs (or trying to).

Post by oldjapanesebikes »

That is a nice looking L model you have there - it looks like you even have the original owner's manual ! :up: Note that if they are the original carbs, they are a one year only set up for the tuning, and a bit different from the later ones ('75 through '77) eh ? The differences are listed in a couple of places - this is one link. Take a look at the carb and the tune up sheets.
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Re: re-installing GT750 carbs (or trying to).

Post by J Backlund »

oldjapanesebikes wrote:That is a nice looking L model you have there - it looks like you even have the original owner's manual !
It looks better in the photo than it really is. There's a bit of corrosion here and there on the frame and misc chassis parts. The front mounting tab for the plastic injector oil tank has broken off the frame from rust, that will be a fun little detail to make right.

I think the owner's manual is for a GT750M, but I have an old Clymer manual for it too. It also came with an original suzuki Gt750 factory luggage rack, which is a nice little item to have for it, though I'm not sure I'll put it back on the bike right away.

If I had the money to do it, I'd just send the entire bike off to a good restorer and just say 'make it new', write the check, and keep it forever.

Maybe in the next year or so, I'll see if I can come up with the cash to buy an already restored GT750, I'm especially fond of the 'L' and 'M' models.
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Re: re-installing GT750 carbs (or trying to).

Post by T350guy »

The boots on my are starting to get hard but not bad yet.
What I did was use a hot air gun just to warm them up and they popped in nicely.
New boots for mine will be replaced shortly as well.
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Re: re-installing GT750 carbs (or trying to).

Post by J Backlund »

Well, I got the carbs back on. Next, get the throttle cables hooked up, then the airbox and filter, battery cage, battery...then the exhaust system......get a few new spark plugs in.....gas......turn the petcock to 'prime' for a minute or two. push button and see what happens.


If all that goes well, I'll get the rear wheel back on, find a new 'X' ring drive chain for it (tossed the one that came with it, a piece of worn out crap) finally get the title transfered into my name, put a plate on the whole mess and try to ride it.

I think that the first 'firing up' will happen (or not) next weekend.
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Re: re-installing GT750 carbs (or trying to).

Post by Barry S. »

J Backlund wrote:
oldjapanesebikes wrote:That is a nice looking L model you have there - it looks like you even have the original owner's manual !
If I had the money to do it, I'd just send the entire bike off to a good restorer and just say 'make it new', write the check, and keep it forever.
But what fun would that be. :up:
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T350guy
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Re: re-installing GT750 carbs (or trying to).

Post by T350guy »

Thanks to pearljam724 for the link in his post.
I bought a set from cruzinimage_co and they were here must say fast.
I put the boots on today and they DO fit nice But the clamps are useless, they skip once you try to tighten so keep your old clamps and reuse them.
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Re: re-installing GT750 carbs (or trying to).

Post by pearljam724 »

Huh, I didn't have that problem. Did all 3 do the same ? None of mine did.
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