help with this clutch!?

[timbo]

Does anyone know what kind of clutch this is? And if so, it takes some kind of lubricant that I need to replace, does anyone know what I need to put in there to replace the old stuff. This is an old Honda engine that I got from a go kart race track place. I actually got the thing to run like a champ!

 

[timbo]

More pics of the clutch. Same clutch....different motor. I used the two motors to make one.

 

[mikeandike]

that is a speed reduction gearcase. i don't know if it has a clutch in it. If youre going to be replacing the lube i suggest to look around on the internet. It looks like a honda reduction gearcase.

 

[timbo]

speed reduction? I don't like the sound of that. how much slower do you think it will make the kart go. and why would there be a speed reduction gear box on it? should I get rid of it?

 

[ryf]

speed reduction is FINE. just don't go little sprocket to big sprocket on the rear axle (IE 12 tooth motor side to 60 tooth axle side) as that is what the reduction box did for you.

I'd look for a part number, make sure they are the same, or at least the same ratio when you look up that part number, I would assume they are.
assuming its a standard 8.7 reducer, if you have 11" tall tires, if you use a 1 to 1 ratio on your chain or pulleys, you'll get about 14-15 mph at 3600 rpm (usual max)

so you may want to use use taller tires. a 16" tire (small riding mower rear tire) is about 21-22 mph and is about the same as 1.5 to 1 change in ratio (within 1 mph), 22" (cheap offroad balloon tire) will be 29-30 mph same as 2 to 1 ratio.

this is "raw" ratio, I'd knock off 2-3 mph for load and slippage and tire squat, if you can roll with the tires you have, gear ratio change will loose you less speed that tires (less rolling load and mass/inertia) so smaller tires with the same top speed will also have a slightly better acceleration. hope that helps.

 

[ryf]

I did a search and found honda also have 6 to 1 ratio...

so if I were you, I'd start at 1 to 1 because it will make a big difference on torque, and you can change that cheap enough if its not where you want it. as it was from a gokart, 6 to 1 makes a little more sense.

if you have 11" tall tires, if you use a 1 to 1 ratio on your chain or pulleys, you'll get about 21-22 mph at 3600 rpm (usual max)

a 16" tire is about 31-32 mph and is about the same as 1.5 to 1 change in ratio
22" will be 43-44 mph same as 2 to 1 ratio.

 

[timbo]

I have no idea what all that means......I know that sounds like I'm stupid or something but if you could explain it like I'm a 1st grader or something please. I do have a small 12 tooth sprocket coming off the gear box to a large 60 tooth on the drive wheel, and my tires are probably eight or ten inches from the the ground to the top of the tire they're the nobby kind like on the old three wheelers. I'll go take pictures of it and try to upload them. Maybe I should just take the gear box off and buy a cent. clutch. The small engine mech. that looked at it said it was a "liquid" clutch, does that sound right? I just want it to work for my kids at this point.

 

[timbo]

here are some pics I just took. This is the parts motor it is not mounted but is exactly the same as the one I plan to use, I was trying to mount the engine plate. I guess the tires are bigger than I first thought. I think I should just remove the gear box and make it easy on myself all this ratio stuff is killin' me!

 

[timbo]

here's another pic

 

[mikeandike]

if start the engine and the gear reduction box output shaft is spinning, then theres no clutch unless there's some kind of lever. If its spinning at idle and there's no lever (i doubt there is one) then the guy you talked to has no idea what hes talking about. I would probably take it off if it has no clutch in it but it would be a good idea to save it.

 

[ryf]

thats not gonna work for you... change that 60 tooth out for direct mount 12 tooth or so, or you'll be doing 5 mph assuming 6 to 1 with what you've said... 24-25 mph assuming 6 to 1 at 3600 rpm on a 14 inch tire.

OR you can take off the gearbox and use what you have. that'll get you 29-30mph. this seems like the cheaper option as long as the shafts are the same (usually are)


think of it like this, someone decided, why use a chain for gearing when I can use a gearbox, you're getting about the same result, and a gear box will last longer in most cases. the problem with what you're doing is you're achieving the same goal twice. the gearbox and your sprocket choice are over reducing your rpm. make sense?

 

[ryf]

http://smallenginewarehouse.com/images/manuals/GX120-200.pdf

check out pages 28/29

10w30 for the oil, change it warm.

if thats what you have its 2 to 1, so with current configuration, 15mph raw max speed.

its a wet clutch transmission possibly. very neat idea

 

[timbo]

that looks exactly like what I have. I feel much better about the whole thing now. Thanks alot for all of your help. 15 mph is a good speed I think, for kids that have never driven a kart before. When they get bigger I can remove the thing (tranny clutch) and move the engine mount and buy a cent. clutch for them, that will make it go faster. Why do you think they put a 1/2 reduction why "slow" it down?

 

[ryf]

the benefits are endless, chains last longer for one. moving at half the speed at the drive end is less wear and tear. wet clutches last alot longer when maintained well. smaller sprockets on the axle = more ground clearance. they probably figured, if we are gonna put a wet clutch in, why not put in a reducer too. if they work, I'd keep them, if you do get rid of them, get a CVT (comet 30 through 44 series for example) instead of a centrifigual clutch, if the kids have graduated from going slow, they get better top end and torque on takeoff, its variable output.