warped sprocket. 415 vs #41 chain. skyhawk stage 3 clutch. etc...!

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gcruiser

New Member
Jul 27, 2010
9
0
0
Truckee, CA
Aloha- Having a good time building my bike. having some issues with my 56 tooth sprocket. mounted it w/the rag joint,teeth outside. put on the 415 chain and it just wouldnt stay on the sprocket. it kept riding up so the teeth were on the in/outside plates of the chain and binding. It would go from too loose to too tight. Thinking this bent my sprocket? I look at the sprocketfrom behind the bike when I spin the
wheel and it waves left and right! So I disassembled the sprocket kit, reversed the sprocket so the teeth are inside(closer to the spokes). slapped it back together,did the coat hanger aligning trick. its concentric but still a little flappy. chain actually stayed on pretty well so I tried it down my street. Hit a snag here. I fired up the engine, let it run for a while. pedaled down the road, pulled in the clutch and felt it sort of engage but then stop. it keeps doing that! dont know if I sheard the driveshaft/clutch key...will scope that out tomorrow.

Thanks to anybody reading this! I have a few questions for you all:

1.can the #41 chain be used with the factory 9-hole sprocket? are there advantages to that?
2.can a stock 56 tooth steel sprocket be straightened out? any recomended methods?
3. can the clutch be engaged with a standard mountain bike shifter/brake lever combination? gonna try that out.
4. are there any shops that provide parts in the tahoe/reno area?
5. any really goodchain tensioner/guide designs out there? like dirtbike style for smaller chains?
6. any tips on proper jetting a huasheng 142f carb. for riding at 5500-6000 feet?
7. where can i find some cool chrome bullet style lights?
Can't wait to get this bike together and ride! Thanks for any advise!
-Greg
 

MotorbikeMike

Dealer
Dec 29, 2007
477
3
18
Sacramento
Hi Greg I am in Sacramento. I imagine that I am the closest Motor Bicycle source to you. Ypu did not say what kit you bought, so I am a a little bit of a loss as to what to tell you.

The 56 tooth sprockets (just like all of the Chinese rear drive sprockets) are sometimes kind of "potato chipped" when received.

Some people have put them on flat surface, and put large board over them, and pounded them flat, tho I have not tried this.

IF it is a 4-stroke you should NOT be pedaling and dropping the clutch, as the only one I know of in production with a "clutch" lever will break by doing that.

What kit do you have?

Mike
 

KCvale

Well-Known Member
Feb 28, 2010
3,966
57
48
Phoenix,AZ
Aloha- Having a good time building my bike. having some issues with my 56 tooth sprocket. mounted it w/the rag joint,teeth outside. put on the 415 chain and it just wouldnt stay on the sprocket. it kept riding up so the teeth were on the in/outside plates of the chain and binding. It would go from too loose to too tight. Thinking this bent my sprocket? I look at the sprocketfrom behind the bike when I spin the
wheel and it waves left and right! So I disassembled the sprocket kit, reversed the sprocket so the teeth are inside(closer to the spokes). slapped it back together,did the coat hanger aligning trick. its concentric but still a little flappy. chain actually stayed on pretty well so I tried it down my street. Hit a snag here. I fired up the engine, let it run for a while. pedaled down the road, pulled in the clutch and felt it sort of engage but then stop. it keeps doing that! dont know if I sheard the driveshaft/clutch key...will scope that out tomorrow.
Whew, lot of questions ;-}
You said a SkyHawk motor and a hand clutch, so I am going to assume a 48 or 66cc Grubee 2-stroke kit.
You don't mention the bike however, and pics really help.

The rear sprockets in the Grubee kits are pretty beefy and not plagued with poor casting problems I hear the cheap kits can usually have so I a thinking it is not the sprocket being bent.
The only way to tell is with it off on a flat surface like a kitchen counter or table and look.
If it is bent you can try the hammer approach, but if you want a new one with the rags I am in Phoenix and have a new one I didn't need I can probably ship to you in a flat padded envelope for $20, drop me an E.

Without seeing the hub all I can do is guess here...
Does the sprocket center hole fit perfectly over the hub? Or is there slop in it?
If the sprocket hole is bigger than your hub you will always have problems like the 'chain gets loose then tight again' problem. The spokes have a hard enough time transferring the motor torque to wheel, trying to keep the sprocket centered too is just too much.

Keeping the sprocket from wobbling is usually just of a matter of slowing torquing the nuts down in a nice star pattern until the sproket is snug against the hub.
1.can the #41 chain be used with the factory 9-hole sprocket? are there advantages to that?
Yes, KMC 410H heavy Duty 'Freestyle' BMX chain work and good stuff.
3. can the clutch be engaged with a standard mountain bike shifter/brake lever combination? gonna try that out.
If you mean use the brake lever as clutch lever sure it will work, but without a lock button you will soon find that very tedious.
Some guys the combo 3-speed thumb shifter/brake combo and hook the clutch to the shifter, I have not tried this but I suppose this would work.



It just seems like a pretty short handle to operate the clutch, and it locks when you pull it whether you want it to or not.

I just use a dual pull tetter-totter self adjusting hand brake on the right, the locking clutch, and just move the little 3-speed twist shifter in a bit on the left like this.





Works great for me as I don't need the clutch to shift my jackshaft 3-speed hub shifter with my left hand, nor do I need the gas when I put on both brakes with my right hand lever.
5. any really good chain tensioner/guide designs out there? like dirtbike style for smaller chains?
The absolute best drive side chain tensioner is to DON'T USE A DRIVE SIDE CHAIN TENSIONER!.
Get back to us with your hub pictures.
When you solve the sprocket sprocket problem and dump the tensioner, all your problems will go away ;-}
 

eldo

New Member
Aug 23, 2009
93
0
0
74
illinois
Got #41 chain on 60tooth sprocket works good. Dont knowif this is the wright way to do it or not but when I put my bike together I didnt tighten the motor mount brackets real tight not loose but they could move if something was out of line ran it for severeal miles then put the Mo on them seemed to work chain stays on. I did notice when I got flat had to line up rear wheel exactly the way it was or it didnt like it.
 

gcruiser

New Member
Jul 27, 2010
9
0
0
Truckee, CA
the grubee (stage1+2???) had a 'clutch' lever that was actually a dis-engager,,,
most rigged them to always be engaged
Is keeping the clutch always engaged a good way to go? That would make it more like my old(go-cart style) minibike which had a centrifugal clutch. could you start the engine by rolling that way? any disadvantages to that setup? I have a huasheng 142f 4 stroke with a skyhawk stage 3 gearbox.

Thanks!
-Greg
 

gcruiser

New Member
Jul 27, 2010
9
0
0
Truckee, CA
which 4 stroke has a clutch lever,I am interested
The grubee Skyhawk stage 3 gearbox mounted on a huasheng 142f 4-stroke is my setup. I havent been able to drive it yet cuz of my chain issues....but soon. The lever just engages the clutch and then you push a button to keep the lever squeezed in. Its basically like shifting into 1st gear on a motorcyle... just gets it in gear.
 

Davee930

New Member
Jun 13, 2010
11
0
0
Calgary
My 56 sprocket came shipped with a couple teeth bent in the wrong direction. This caused the chain to jam every revolution so I had to take off the sprocket and bang the teeth with a hammer. This worked well and everything is smooth now.
 

ferball

New Member
Apr 8, 2010
598
2
0
NH
I have my shimano rapid fire shifter for my front derailer going to my clutch, works like a dream
 

phoobarnvaz

New Member
Oct 28, 2008
252
2
0
Colorado Springs, CO
Hi Greg I am in Sacramento. I imagine that I am the closest Motor Bicycle source to you. Ypu did not say what kit you bought, so I am a a little bit of a loss as to what to tell you.

The 56 tooth sprockets (just like all of the Chinese rear drive sprockets) are sometimes kind of "potato chipped" when received.

Some people have put them on flat surface, and put large board over them, and pounded them flat, tho I have not tried this.

IF it is a 4-stroke you should NOT be pedaling and dropping the clutch, as the only one I know of in production with a "clutch" lever will break by doing that.

What kit do you have?

Mike
I've got the HS 142F with the Stage 3 gearbox. We were shearing pins on the drive shaft right and left from engaging the clutch while pedaling down the road. After getting pissed off and giving up on trying to get it running...took off the 4 stroke and put on an 80cc 2 stroke.

Could you or someone else explain the steps to lock this gearbox in the engaged position...possibly with photos? Would love to use my 4 stroke again.

Thank you for your help!
 

ocscully

New Member
Jan 6, 2008
373
1
0
Orange County, CA
It's really a pretty simple process. I use a brake straddle cable yoke, but any type of cable anchor will do. Pull the cable thru the adjuster on the gearbox to fully engage the mechanism, then slide the anchor against the adjuster and tighten, cut off the excess cable. I also used to reverse the springs on the engager yoke as well. This way if the anchor slipped the springs would work to keep the engager ingaged.

ocscully
 

phoobarnvaz

New Member
Oct 28, 2008
252
2
0
Colorado Springs, CO
It's really a pretty simple process. I use a brake straddle cable yoke, but any type of cable anchor will do. Pull the cable thru the adjuster on the gearbox to fully engage the mechanism, then slide the anchor against the adjuster and tighten, cut off the excess cable. I also used to reverse the springs on the engager yoke as well. This way if the anchor slipped the springs would work to keep the engager ingaged.

ocscully
That's almost too simple. Wished I knew about it before.

Thanks for all the help!!! Will save me from putting on another 2 stroke China Girl or a pocketbike engine.
 

phoobarnvaz

New Member
Oct 28, 2008
252
2
0
Colorado Springs, CO
It's really a pretty simple process. I use a brake straddle cable yoke, but any type of cable anchor will do. Pull the cable thru the adjuster on the gearbox to fully engage the mechanism, then slide the anchor against the adjuster and tighten, cut off the excess cable. I also used to reverse the springs on the engager yoke as well. This way if the anchor slipped the springs would work to keep the engager ingaged.

ocscully
Just got the springs reversed and is holding the engager engaged. The freewheel is going to need to be replaced...but no biggie.

Is there any type of splined shaft that I can replace what it came with to not need to worry about keys anymore?
 

KCvale

Well-Known Member
Feb 28, 2010
3,966
57
48
Phoenix,AZ
Just got the springs reversed and is holding the engager engaged. The freewheel is going to need to be replaced...but no biggie.

Is there any type of splined shaft that I can replace what it came with to not need to worry about keys anymore?
I am not familuar with your gear setup at all, but I can share this about gears going on a shaft with a shear pin notch.

Does it have 2 set screws?
One over the key, and another 90 degrees off?

If so, you file down a flat notch at the spot it tightens to on the shaft with the edge of a file where the set screw leaves a mark on the shaft.

That's what we do on Jackshaft gears and shafts.
It gives the gear more shaft grip.

I have new pics of of that very thing from the build I am doing now but my PC is down, I'm on a laptop and do pics today, but I have pics in one of my other JS project builds.

Again, I don't know your setup at all, just passing on the tidbit just in case it helps someone ;-}
 
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phoobarnvaz

New Member
Oct 28, 2008
252
2
0
Colorado Springs, CO
I am not familuar with your gear setup at all, but I can share this about gears going on a shaft with a shear pin notch.

Does it have 2 set screws?
One over the key, and another 90 degrees off?

If so, you file down a flat notch at the spot it tightens to on the shaft with the edge of a file where the set screw leaves a mark on the shaft.

That's what we do on Jackshaft gears and shafts.
It gives the gear more shaft grip.

I have new pics of of that very thing from the build I am doing now but my PC is down, I'm on a laptop and do pics today, but I have pics in one of my other JS project builds.

Again, I don't know your setup at all, just passing on the tidbit just in case it helps someone ;-}
Gonna get this old type of gearbox off my HS for a belt drive that should outlast/outperform anything from Grubee.

As for the freewheel...if I remember right...it's got a groove cut into one side of it where the key fits. The whole freewheel is held on by a bolt through the middle of it.