Urgent help needed with Jackshaft / Chain Problems (Predator 212cc)

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KCvale

Well-Known Member
Feb 28, 2010
3,966
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Phoenix,AZ
Cool, glad to hear you are fixed up, I had some time so I covered everything I could think and here's for the next guy with a similar problem ;-}

One other note is you are going to JS anyway and mess with gear ratio try a real Jackshaft and use the bikesl gears, it changes everything.
 

Predator303

New Member
Apr 26, 2012
648
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San Juan, Puerto Rico
Works great with 3in1 on the clutch for 3 min ;) On monday I will go to a local store to see what clutches he got and how much they are. If its too expensive I will just order online and wait 4-5 days more.
 

sportscarpat

Bonneville Bomber the Salt Flat record breaker
Jun 25, 2009
1,839
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california
I didn't read this entire thread but Jeff was on the money with gearing being too tall. You can typically push anywhere from 10:1 to 14:1 with a centrifugal clutch and GX200 build, at least with the disk type. Shoe type clutches vibrate more than a disk style but still, once it's locked it's locked and the vibration is gone. Trick is to get this lock happening at about 3400 rpm and GETTING THROUGH TO FULL LOCK QUICKLY. This is done with proper gearing. Try a 38 tooth primary sprocket on your jackshaft.
 

Predator303

New Member
Apr 26, 2012
648
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0
San Juan, Puerto Rico
38 on the jackshaft? that sounds way too short the ratio. i only use the 15 right now because the 22 was damaged by the engine/clutch. i am planning to order 2 different one piece sprockets again for JS-in. one 20t and something around 18t for longer ratio. lets see what i get monday in the shop. i think i will end up having to order online and waste another week again... at least im getting done with it soon. after all it is a custom build and that stuff happens.
 
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Predator303

New Member
Apr 26, 2012
648
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0
San Juan, Puerto Rico
I went today to a bunch of shops to buy a new clutch and turns out all the Max Torque clutches all have metal shoes too. Anyways, I bought different sprockets for shorter gear ratio and another cheap standard clutch for testing and have to wait - once again - until the weekend to get it all...

Buh
 

Predator303

New Member
Apr 26, 2012
648
0
0
San Juan, Puerto Rico
Otherwise there might be motor movement, hold your frame top bar with hand hand and shove you motor back and forth AS HARD AS YOU CAN, if it moves AT ALL start there because nothing else down the line will work.
hey man. i didnt notice it before but it DOES move. not much, but enough to be another cause to cause the problem is low rpm until the clutch engage. i didnt notice it before but now that i have the stock muffler on it which is very close to the top frame, i can use one hand and it really does move because its only welded in the bottom and not in the front.

anyways, today i got a 20t sprocket for JS-in and a max torque clutch. the max torque clutch was a little more gentle at first but then same shhhhh..

so yeah i need to get my ratio closer to 9.000 (right now its 7.300) how david had it before and maybe one of those more expensive adj. clutches. either that or the agk solution with a modified max torque clutch, but that was tested on a 99cc predator, not the 212cc:

"Earlier in the article we mentioned some vibration we experienced when the clutch would try to engage. Vibration is not only annoying, but can cause other issues with the bike, so here's the low down.

There are two methods we use to reduce vibration upon clutch engagement. One way is to increase the stall of the clutch. The clutch we sell for the 99cc Predator has wedge shoes with a black spring which provides a 2800 rpm engagement. By installing regular shoes in our Max Torque clutch we get full lock up at 3100 rpm. This really smooths out the engagement and makes the bike so much more enjoyable. However you don't want a clutch with a 3100 rpm stall if you still have the governor in your engine. That would not give you much of a operating rpm range."

not sure if that would be enough for me but i would love it because the clutch is inexpensive and i really would like to avoid spending another 150+ only on the clutch.

so yeah, now also my 10t JS-out sprocket is damaged by the vibrations and i have to order that one too - again. so another 1-2 weeks im stuck with this $#@$#@$....

im also planning to order a 25t JS-in sprocket. i finally found a place where they sell them in one piece like the smaller once without the hub they use for the 22t sprockets. that would be here if anyone was searching for that:

http://www.usabearingsandbelts.com/18m7/sprockets/35-sprockets.html

im extremely frustated and also cut out a piece of flesh of my thumb today, trying to get a sprocket off. the bike is DONE but for those little annoying details i cant use it.

i was able to ride it once today though and for the first time able to pull the clutch full power after i slowly got to 15mph on a longer straight and the vibrations stopped. HOLY MOLY!!!! this is far beyond everything i expected in power. it is absolutely crazy and dangerous so much power on a bike frame haha. this bike will smoke most of the cars out there in terms of acceleration. very impressive! so now back to waiting..
 
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