High rpm Clutch

[r97]

If you run 2 shafts you can use nothing but standard clutches and sprockets besides the one way.

i was thinking about that and..... yes you can, but for a 2 speed jack shaft it may be worth just trying to squeeze 2 cent clutches on the engine shaft, but if you were to build say a 4 speed one you would need a jack shaft.

 

[r97]

okay heres the pics, this is for a 2 speed setup,

gray=clutch1(1800 rpm engagement), gold=clutch2(3000rpm engagement), brown=chain1, orange=chain2, light green=free-wheel sprocket1, purple=tandard sprocket, pink=standard sprocket2, red=axle sprocket1, dark green=chain3, only problem i can see here is trying to fit 2 cent clutches on one engine shaft, but doing so will eliminate 1 whole jack-shaft. a three speed version could be made by running direct chain drive from engine to jack shaft then putting one clutch for ever "gear" of the transmission(each clutch's spring tensions would be adjusted to engage at a certain rpm, each clutch would drive a free-wheel sprocket on a second jack-shaft, with the exception of the last "speed" which would have a standard sprocket instead of a free-wheel sprocket, then a standared sprocket at the other en of the jack shaft that would drive the rear axle through a final gear ratio, i believe this is a much more "diy friendly" setu to build compared to the average 2 speed jack-shaft, i may just have to make one!

 

[hawk1093]

Thank you so much! this is so cool! Only one thing how does the light green sprocket work? Is it a one way? Where do I find a sprocket like this.
Thanks again

 

[r97]

yes its a "one way" sprocket also known as a free-wheel, any bike you own has one, it basically enables you to coast. are you making a 2 speed or a 3+? after knowing that i can give you a parts list.

 

[hawk1093]

Probably just a 2 speed for know. I have 1 minor problem no way am I going to fit two clutches on my engine shaft. Does that mean I will need 2 jackshafts?

 

[modelengineer]

for a 2 speed jack shaft it may be worth just trying to squeeze 2 cent clutches on the engine shaft, but if you were to build say a 4 speed one you would need a jack shaft.

They would need to have different engagement rpm, and the lower geared one would need a one way bearing installed. Easier to put one on a jackshaft IMO.

Easiest would be a bike engine swap, as that has the best clutch, a gearbox, more power, etc.

 

[r97]

yea i know that, i just though i wouldn't mention it until it needed to be mentioned.
one bike free-wheel with adapter hub(you can also buy different size sprockets if you want a different first gear ratio, just let me know and all get you some links), http://www.staton-inc.com/store/products/22_Tooth_freewheel_1_2_x_1_8_two_spot_welds-701-25.html
two 10t 3/4" bore #40/41 chain cent clutches with keys(one you will need to tighten the springs)
three 10t #41 chain sprocket (one bored to fit your engine, the other 3/4" bore) all with set screws and keys
one 5/8" bore #41sprocket (#of teeth can be your choice depending on what you want your second gear ratio to be)
one 3/4" dia jack shaft with bearings & locking collars.
one 5/8" dia jack shaft with bearings & locking collars.
two 5/8" dia locking collars
four 3/4" dia locking collars
one more 3/16" key about 1" long
several feet of #41 chain (i'm 95 percent sure this chain will fit on the bike sprocket, can someone verify?)
one 5/8" bore sprocket, and one axle sprocket (these make-up your final ratio)
thats everything! take lots of pics!

 

[hawk1093]

Right thanks for all this. I was thinking a ratio of 6:1 for 1st gear (that's what I have on my kart now) and maybe a ratio of 4:1 in 2nd. What do you think?
What size sprockets will I need to achieve this?

 

[hawk1093]

Also I would appreciate a sketch of setup3 if possible, I know what your talking about but those sketches are alot better than I can draw and I like having a picture to work off of.
Thanks!!

 

[r97]

60 to 40 seems like a bit of a big jump, but you it will prob work out fine, if you are un-happy you can always get a different sprocket, if you tell me what your engine size is and its max rpms, the terrain you wish to ride on, and your current wheel dia i can make the necessary adjustments to the above.

EDIT: the only other potential problem i can think of is the bike free-wheel not being able to handle the rpm, but you'l find out! lol

 

[hawk1093]

Yeah reeeaal funny,
Ok, engine is a HondaGx200 6.5hp, max rpm is approx. 3600, terrain will be hard dirt and sometimes grass a few uphills but nothing that steep, and finaly my wheel diameter is 12"

 

[r97]

are you happy with the low end right now?

 

[hawk1093]

Yup, it is fine I can do 0-full in about a two hundred feet

 

[r97]

ok heres the pics, sry i can't give you a description, or ratios, but i will as soon as i get home from school tomarrow,

EDIT: i will also check to see if 41 chain fits on bike sprockets, and maybe do some research on how many rpm a bike sprocket can handle.

 

[hawk1093]

Thank you sooo much (once again a marvelous sketch) I can't wait to get started, this is going to be AWESOME!!!
BTW I am pretty sure that 41 chain fits the bike sprocket,
because I have an old bmx bike and I checked it's sprocket it seems to fit.

 

[redsox985]

Use #40 not #41. They have large strength differences, #40 being stronger.

 

[Blazkowiez]

If possible use #420 if you're discussing bike sprockets, perhaps even #428 if it drops down fully.

 

[r97]

ok, so i showed two pics, first is with the second jack-shaft horizontal to the first, the second pic is with the second jack-shaft above the first(didn't have time to re-draw chains), both are perfectly fine. ok brown sprocket is #40 3/4" bore 10t, orange is#40 3/4" bore 10t, blue clutch is 3/4" bore 10t #40 chain with springs removed and tightened until you get them tight enough so that it only engages at 2000 rpm, green clutch is #40 10t 3/4" bore, purple sprocket is 14t 5/8" bore #40 chain, yellow sprocket is bike free-wheel with 5/8" keyed hub, pink sprocket is 14t 5/8" bore #40 chain, red axle sprocket is 1" bore (assuming you have a 1" dia keyed live axle)40t #40 chain, first jack-shaft is 3/4" dia, second jack-shaft is 5/8" dia. this will give you a low end ratio of 6.29 to 1, and a high end ratio of 4 to 1.
parts list:
two, 3/4" dia jack-shafts (one needs to be at least long enough for 2 clutches & sprocket linked to the engine, the other can be a bit shorter) with bearings, weldments, and locking collars, can be purchased here
two 3/4" bore 10t #40 sprockets, can be purchased here
two 3/4" bore 10t #40 clutches.
two 3/4" bore 14t #40 sprockets.
one of these and one of these these work with each other
one 40t #40 1" bore (assuming you have a 1" live axle), can be purchased here
several feet of #40 chain (how much depends on where the jack-shafts are placed, but trust me you'l need a decent amount)
you will also need keys for all the sprockets (and maybe the clutches)
also make sure all the sprockets come with set screws
6 3/4" locking collars to keep clutches in place on jack-shaft and to keep free-wheel in place
and obviously a way to weld the jack-shaft weldments onto your frame!
few more parts sites,
http://www.gokartgalaxy.com/
http://gokartnminibikeparts.com/
http://www.bmikarts.com/
http://www.mfgsupply.com/m/c/index.html?id=pEUfkUHW
http://www.agsupplyonline.com/
if you can't find one of the parts tell me and i will try to find it for you

EDIT: just checked #40 does indeed fit on bike sprockets

 

[devino246]

#41 chain doesnt fit bike sprockets. Its way too wide. Im not sure about #420 though. This looks like a very expensive setup.

 

[hawk1093]

Thank you so much for this. Now let me get this strait 40 does fit the bike sprocket but 41 does not? That's my only question, if I have anymore I will let you know. The only problem is I don't get paid untill October, by the time I get all the parts and get it built it will probably be close to December. Once it is done I will be sure to post pics,
Again thanks to all who helped with this post, especially r97