1977 GS 750 mutt..Carb problem/identification.

[chuck hahn]

Hey Josh...If he gets these 26s from me, there shouldnt be any problems with connecting the throttle cables would there? Im thinking not but a second opinion never hurts.

[koolaid_kid]

TCK is correct, you will want a new set of intake manifolds with new o-rings.
Chuck's offer is a heck of a deal, and no, unless you are a skilled carb tuner you won't find anything better out there.

[chuck hahn]

If you decide to get these carbs..also have Robert send you a set of intke boot orings..have him send me the orings for the VM26s.

[banshee]

If you decide to get these carbs..also have Robert send you a set of intke boot orings..have him send me the orings for the VM26s.

Will do thanks for all the help. I am unsure if the bike is actually 1000ccs or 750cc what would you guys do tune for 750 or 1000cc

[chuck hahn]

Well I can verify whats in them and then youll know in case you find its the other bore..then all youd have to do is swap out whats in here for the right ones later. Give me a few to open one up and tale a looksee.

[tkent02]

Those are NOT BS 32s... Those are great carbs.

[banshee]

Are these the O-rings you need? I am going to go ahead and order tonight and have the shipped to you. http://cycleorings.com/VMkit.html

[TheCafeKid]

Do you know for sure what was done to it? I checked the compression and I got between 165-175 PSI on all 4...Seems high to me, maybe the head was milled? . My compression gauge is accurate, I cross checked it with my 4mil banshee after to ensure it was still on point. To me it looks like someone loved it, then someone started jacking around. As far as I can tell the swing arm was done right. The gauges and signals are all modern, but they are all functional and correct. Someone fabbed some nice looking exhaust brackets to worth with the aluminum
swinger, and some nice brackets for the modern gauges.

No idea. I just saw pictures. Things you'll want to check are things like assuring the wheel is in line with the front wheel, chain alignment is correct, pivot bearings are smooth and there's no slop in the pivot, steering mast bearings are kosher, etc etc.

There are LOTS of threads on upgrading these bikes using modern suspension and running gear, and some AMAZING bikes have been put together (isleomans, posplayr, and all of Katmans bikes are stunning examples just to name a few) but there are a lot of things that you can seriously screw up and make the bike handle like crap, or worse, be a death trap. If you can, just for our own curiosity, take some better pics of whats going on with that thing and we might be able to point out any issues, if there are any.

I don't know for sure, but the carbs may be slingshot carbs or the like. Either way they look like they need to be cleaned up. Im not trying to stomp on Chucks sale by any means, but I'd see what you can find out about what those are, and what's been done to the motor before making any changes.

As for your compression numbers, a cold test means little. The bike needs to be warm, and then tested by turning the motor over with the throttle wide open (but not running) to get an accurate reading....

Fill us in on what you figure out, it is an interesting little monster that could end up being an awesome runner when you get it sorted.

[chuck hahn]

Im not really trying to sell anything as much as help the guy out. If he wants to keep those then thats cool too. I just figured since i got stockers laying around collecting dust then why not offer a set up.

[TheCafeKid]

Im not really trying to sell anything as much as help the guy out. If he wants to keep those then thats cool too. I just figured since i got stockers laying around collecting dust then why not offer a set up.

Oh no it a totally cool and generous offer from you Chuck, like I said I wasn't trying to undercut you or anything of the sort. But if it turns out that motor has a bunch of head work and big pistons and such, and those carbs are better for his set up than stockers, he wouldn't want to mess that up. I'm just saying he should dig in and see what's going on before making any decision about anything. That's what I'd do anyway. Who knows? It could be a stock motor and those carbs aren't doing him any good, if not bad. But without documentation, someone could say they had done this that and the other thing to it and you'd not be able to tell in most cases without cracking a cover or two open...

[chuck hahn]

How would he verify short of pulling the head and measuring the bore and stroke??? Im sure he isnt into that much tech work.

[banshee]

I can always jet bigger with the stockers, if the guy really did do some work. This is my first four stroke so I am not really wanting to split the cases if I can avoid it.

[koolaid_kid]

You would not have to split the cases, but you would have to pull the head. It can done with the engine in the frame, but it is not for the faint of heart. Procedures can probably be found in the factory manual, which you can get from BassCliff's web site. This is the only way to verify displacement because you need to measure both the diameter of the bore and also the stroke.

[TheCafeKid]

Tell tale signs of head work would be slotted cam sprockets, polished or cleaned up intake runners...which can be seen without pulling the head...

Sure you could jet 26s for whatever is in it, but A) if it does have work done, it's a waste as the carbs choke it off and B) you'll have to guess at where to start jetting....

Pulling the head isnt hard, or daunting, if you have any mechanical skill whatsoever. It's certainly no harder than re-jetting carbs for an engine of unknown displacement...

But, again, it's your bike, do what you're comfortable with.

[rustybronco]

Is that a 4 into 2 exhaust on that bike?