Engine shaft question... HELP!

[MNTravis]

I need some advice here!! I got my brand new Honda GX670 for my custom cart the other day and finally got around to messing with it. UNFORTUNATELY when I put the clutch on and sat the engine up on the frame of the kart it became quickly evident that the driven and drive clutches were way off from lining up with each other. What it comes down to is the fact that the shaft on the Honda is 3.5" long and with the way the inner shaft of the Comet clutch driver clutch is built, it only takes in 1 9/16" of the shaft before it bottoms out and will not go in any further. So then the clutch sticks way out and there is no way I could line up the two clutches even with the engine pushed all the way to the right as far as it can go without interfering with the suspension/rear wheel. See the pictures attched.

The immediate option that came to mind was that if I simply cut off 1 3/8" of the shaft, the clutch would then fit on correcty and allow the two clutches to then line up. There would be 3/4" of internal thread remaining on the inside of the engine's shaft and there would be exactly the right length of key left on the shaft for the clutch. Just makes me nervous to start hacking up a factory new engine, but there doesn't seem to be any other choice if I ever want to be able to use the engine for this kart! I assume I could use my portable metal cutting bandsaw (or even a hacksaw if I had to), although the shaft is 1 1/8" thick of hardened steel, the inside is drilled out to 7/16" so it would probably no be too bad of a job to cut it off??

Have you ever cut one of these things off or know if there are any possible problems in doing such?? I am looking for any advice I can get before I make an irreversible move!! What do you think? ANY ADVICE IS APPRECIATED!

[scottyb]

Great pics ...... I'll say cut it off.... but, wait and see what others say first

P.S.
What exactly are you building there? More Pics?

[BigBlockMan]

I would not cut it. Your putting on a clutch from someone thats no longer in buisness. Replacement parts are not available. Lets say your clutch breaks there is no new replacement. Sell it and buy a straight shaft clutch that will fit the motor, One you can buy replacement parts for.

[scottyb]

Originally Posted by BigBlockMan

I would not cut it. Your putting on a clutch from someone thats no longer in buisness. Replacement parts are not available. Lets say your clutch breaks there is no new replacement. Sell it and buy a straight shaft clutch that will fit the motor, One you can buy replacement parts for.

See......... I told you to wait for sounder minds

How about some more pics of this contraption

[rib33024]

Originally Posted by BigBlockMan

I would not cut it. Your putting on a clutch from someone thats no longer in buisness. Replacement parts are not available. Lets say your clutch breaks there is no new replacement. Sell it and buy a straight shaft clutch that will fit the motor, One you can buy replacement parts for.

I would go with what Tom said

get a new clutch -----and sell that one--


And tell us more about that cart

[scottyb]

Maybe it is not a cart..... maybe it is a secret project?
Maybe it is a gold separator

[rib33024]

Originally Posted by scottyb

Maybe it is not a cart..... maybe it is a secret project?
Maybe it is a gold separator

I seen one of them once --only one

scottyb you know your not to be talking about them---

[MNTravis]

Originally Posted by BigBlockMan

I would not cut it. Your putting on a clutch from someone thats no longer in buisness. Replacement parts are not available. Lets say your clutch breaks there is no new replacement. Sell it and buy a straight shaft clutch that will fit the motor, One you can buy replacement parts for.

I hear you about the clutch being from Comet who is now defunct (whic really sucks). I have heard rumors that the company that bought their assets will be starting up production in a year or so, so I have some hope. I actually almost went with the CVTech PowerBloc 80, but all said and done it would be about $800 to get their product in hand. I have faith in the Comet clutch and I am seeing lots of stuff floating around ebay and such, so if in the event I had a problem, I think I could get what I need to get it back up and running.

As for getting a different clutch, as per comet the one I have is the right model for my engine/shaft set up. For whatever reason the STRAIGHT 1 1/8" keyed shaft Comet 94C driver clutch narrows out about 2" into the shaft where the key stops, and just about corresponds to the outside location where the belt rides on the shaft. Even the mounting bolt they provide you is the length needed to not come into contact with the engine shaft until after it passes through about 1/3 of the clutch's width.

The problem 100% lies with the engine compartment of my kart, I have a narrow area that the engine/clutch must fit within or it will collide with the trailing arm IRS setup (see picture) as the trailing arms go up and down as per the red arrows. By cutting it off I am buying 1 3/8" of space which gives me just the right amount of clearance and lines up the clutches and everything else just beautifully.

I really do appreciate your advice though. I was really hoping that somebody could give me some advice about the act of cutting it off, as per the first set of pics I posted. I could take the whole new engine to a machine shop and have it done that way, but I would bet they would want the shaft pulled from the engine; which I beleive would require a complete tear down of the poor little new engine!! My idea was to use my handheld metal cutting band saw, I guess if I tried it and it wasnt working right I could then take the shaft to a machine shop. Does anybody know if you have to teardown the whole engine to get the shaft out?? I love working on engines, but almost cry at the idea of having to tear down a factory new engine!! OR, we could do it cowboy method, start the engine, run it up to 3600 rpm and apply a handheld hack saw to the shaft as it spins away!

[scottyb]

Can a machinist broach cut the clutch to fit all the way on?

[MNTravis]

Originally Posted by scottyb

Can a machinist broach cut the clutch to fit all the way on?

I thought about that, but worried that it tapers in for engineering reasons and having them machine it out would make the clutch inoperable? Anybody know about this, otherwise I will make some measurements, but I suspect that even if the clutch was 1 1/8" wide all the way out I would still have to modify the shaft of the engine?? Guess I need to go do some measuring!