Belt drive

[I like karts]

Im going to use trampoline springs to keep it tightened when the pedal is not pushed

 

[ed1380]

if it stays tightened then wouldnt it be always engaged

 

[Kenny_McCormic]

If its a single speed deal run a spit throttle cable with one end pulling the throttle, the other should pull a spring that is hooked to the tensioner. This will reduce parts count and make it safer/easier to operate.

 

[I like karts]

That's what I'm doing, except it's going to be 2 different pedals and the one that controls the tensioner is like a manual clutch

 

[Kenny_McCormic]

Well, Im the most uncoordinated person out there, I have tripped on myself before and sometimes find myself having to think of how to walk. manual clutch is something I dont think would work out well of me. You might be better off finding a guy parting out a snowmobile and stealing the CVT off that, would go faster.

 

[I like karts]

Nah, I love manual clutches, and I think it's going to go fast enough without a cvt


I used the calculator and 11 inch tires + 8000 rpm + 4:1 ratio = 65mph


And I might be getting like 14" tires later (83 mph )

 

[ironman]

Nah, I love manual clutches, and I think it's going to go fast enough without a cvt


I used the calculator and 11 inch tires + 8000 rpm + 4:1 ratio = 65mph


And I might be getting like 14" tires later (83 mph )

speed racer.........speed racer

 

[AutoMX]

just to clarify regarding the driveshaft water lubrication...

the shaft uses the water pulled in by the turbine to lubricate the o-rings around the shaft. this is why you should not run the ski for more than a minute when not in water...

 

[I like karts]

Im not using that part though. Im just getting the little piece of shaft right off the engine not the prop part

 

[ed1380]

just to clarify regarding the driveshaft water lubrication...

the shaft uses the water pulled in by the turbine to lubricate the o-rings around the shaft. this is why you should not run the ski for more than a minute when not in water...

o. cool. i always though cause the engine might overheat.
no water = no coolant = empty block

 

[AutoMX]

Im not using that part though. Im just getting the little piece of shaft right off the engine not the prop part

yea i know, that stuff should always be dry and greasy

and regarding the running out of water, the ski should never be turned on without the hose hookup anyway, but even with that, only the engine is cooling and the pipes are being flushed out (in case there was salt), it doesn't touch the driveline so thagt stuff is just rubbing the rings dry

either way, should make quite a motor, the 550 is 39hp and they are made to rev real high cuz theres no tranny

 

[I like karts]

Yeah, Im gonna have to widen the back of my kart though I think

 

[modelengineer]

"i like karts", this setup you describe is IDENTICAL to the one i just finished on my kart. I ALSO USED TRAMPOLINE SPRINGS! THey work great, however because of the leverage I had I had to use 2 of the springs. So far there has been no belt wear, and the pulley doesn't get that hot unless you slip the clutch heaps. I will post a picture tomorrow

 

[I like karts]

Wow thats sweet! Im yet to get the engine, just have to go take it out.

Thanks for the info I was kind of worried about belt wear

 

[el~bryce`o]

3 pulleys from a scrapyard were $20, and the belt's are $10. Also, here in Australia the centrifugal clutches are a bit more expensive.
It's all ready to go but the belt I got is too long, have to wait until monday to get another

I know many people here swear by the centrifugal clutches but I don't really like them.

yer aussies's who else is here thats aussie. im using a belt centrifugal clucth on my bsr and im actuall confused how they work

 

[Kenny_McCormic]

yer aussies's who else is here thats aussie. im using a belt centrifugal clucth on my bsr and im actuall confused how they work

At idle the belt is loose, rev it up and the drive pulley gets narrower, tightening the belt and making you go, as the belt get tighter from higher engine rpms it pulls the driven pulley apart which ups the gear ratio.

 

[athif]

unlike chains belts dont make that annoying clank sound or pose a threat to rip your legs apart.

 

[el~bryce`o]

i see now