My electric start full suspension predator 212 build

[KCvale]

Kc so I'm confused a 49cc with a three speed in your opinion won't do 40...
(what) would you suggest for a 5'7" 125 pound girl to be able to hit 40 if need be.

Oh heck ya, with her size she could run 40 on an aluminum frame 49cc shifter easy.
I pretty much base all my speed estimates on a 6' 180+# man on a steel bike.

This Genisis 7-speed for example would be low and light enough for her to handle and do 40 easy.

Heck, I am 6'1 and 165# and did ~45 with a 53cc and better exhaust and spark plug.
For her size dual V brakes could stop her well too.

I am trying to remember spoke count but pretty sure it is over 36 so a direct drive rag joint sprocket won't fit it.

Speaking of which, it is really best to decide if you want to go shifter or direct drive first as it's twice as time consuming and expensive to switch from DD to shifter on a 4-stroke as besides the base, even the bottom bracket needs changed.

Also note that a 7+ speed has about the same gear ratio between high and low as a 3-8 speed internal, just more steps in-between, a thinner drive chain, and it's only in-line in 3-4th.
Dandy for human power pedaling but a waste for engine power.

Hope that helps.

 

[Amarion1]

That genesis is a beautiful bike to work with. I put a 66cc 2 stroke on it with the SBP shift kit and converted it to v brakes. Sold it to my buddy as his daily driver. He's 220 6' and hits 35 40 with how it's set up. The rear hub is trash though. Bent the shaft pretty quick with the shifting. i think it has 48 spokes and the rag works with 6 bolts but is tough to torque down and keep a straightish sprocket. I think your gal would do fine on your steel frame with a 49 kit but I still think the 79 would be the way to go don't know about performance internals though sorry! Get a tach on it and tell her to keep it in a safe rpm range

 

[romerider153]

The bike itself isn't an issue I have already started chopping one up I cut the head tube and laid it back for more rake and lowered the top tube. I have already started an in frame tank for it. I appreciate all the help though there's a ton of knowledge on this forum I just couldn't decide if I should go 79cc or 53cc with a 3 speed

 

[KCvale]

I appreciate all the help though there's a ton of knowledge on this forum I just couldn't decide if I should go 79cc or 53cc with a 3 speed

The 79cc is pretty heavy and bulky compared compared to 49/53cc.

And that's a 29" bike, but with those bigger tires would get to 40 in a hurry with the power.
Might be a bit too much for a petite woman is all.

I am digging the 53cc/10G system with a 3-speed disc.
It has been all I'd hope for so far, now I am taking it a step further...

...designing a drop on system for the new GT2-150 Fat Tire disc gas tank frame, but that is for another topic so I don't on walk yours, just relevant enough to maybe be useful to you regarding your transfer case choices when it comes to jackshaft options.http://motorbicycling.com//www.pinterest.com/pin/create/extension/

 

[romerider153]

Well back to the 212 I made a new chain tensioner for the clutch side so that it tensions on the slack side of the chain. This helped a lot with a driveline vibration I was getting. I also swapped out the small front sprocket on the freewheel side to a 24 tooth sprocket down from a 36 and that really helped however I still have yet to have to shift the bike. I just ordered a 24 tooth to go up from a 17 tooth on the clutch side of the jackshaft so hopefully that gets me where I want to be. I'm also playing with clutch engagement points and I believe I need to go up a jet size however agk is always sold out of them . I may end up just drilling it slightly bigger.

 

[Amarion1]

That sounds good! Hopefully you get what you're looking for. Is that the tensioner on the other page you posted recently? I like that side cover! Did you buy that or paint it?

 

[romerider153]

That's the new tensioner and that is a stock cover that I just removed the big extra boss off of and then wrinkle painted. That smaller sprocket in that picture is the one I'm enlarging going from 17 tooth to 24 so hopefully that gets me down even further.

 

[culvercityclassic]

That's the new tensioner and that is a stock cover that I just removed the big extra boss off of and then wrinkle painted. That smaller sprocket in that picture is the one I'm enlarging going from 17 tooth to 24 so hopefully that gets me down even further.

A few things that would help with the vibration is to replace that tensioner wheel with a #35 sprocket type: Offered from Northern Tool and made by Azusa. All my past builds use this type, makes a big difference. Another thing to consider is a support on top of the motor connected to the frame, the torque with-out the top support will cause vibration. Look at Sportsman Flyer builds and you will see the type of mount I am talking about.

On another note: I would leave the clutch alone as is, you start playing with it and adjusting it will lead to headaches...trust me on that one...lol

After you get that all fine-tuned and can shift that bike you will have one beast for sure.

 

[romerider153]

That aluminum bracket in front of the clutch bolts to the crankcase cover and two big bolts to the frame so the motor is bolted in in 6 spots. Do you think it needs another up top to I assumed that front mount would be enough. And I actually already order that exact tensioner your talking about so I hope it helps. Did you just add some weights to the cheetah and that's it no adjustments of the springs?

 

[culvercityclassic]

I would add the weights to the clutch and not touch the spring height adjustment. Try tensioner sprocket and see how it works. Attached picture shows three contact points on an 80cc motor... Trust us on the mounts, it makes a big difference

 

[romerider153]

Got yea I hadn't seen one there before. Do you have a closer picture of one does it just attach to two valve cover bolts? Thank you for the info.

 

[romerider153]

I swapped the clutch side sprocket and holy crap did it make a difference I actually needed to shift for the first time. I can't wait to get it on a long straight and see what she can do. I am deff going to try that valve cover mount and hopefully my chain tensioner comes in soon. I want to get ride of all the vibration it's not bad but I would fell more comfortable going fast on it if it was as smooth as possible.

 

[Amarion1]

Yeah that's a good idea for another mounting point! I don't know how much room I'll have but I'm going to have to look into that as well! I was going to make a mount like that on my 66 going from a head bolt to the frame but never got to it/forgot

 

[romerider153]

well little update I took the bike out for a high speed run. had a few issues but overall was successful the red roller that tensions the clutch side chain locked up and the chain wore a nice groove into it. that doesn't matter since my tensioner sprocket should be here any day now. It is still geared to tall but first and second are now useable, third gear the motor bogs down it just doesn't make enough power so im going to gear it down further and I think im going to get a cam and a billet rod. The bike on gps did 52.3 at about 75% throttle in second gear so im getting there a lot of trail and error with gear ratios.

 

[romerider153]

Chain tension is done it deff is smoother the only vibration I'm getting now is under partial lock up from the clutch which doesn't bother me since it's only for the first 5 feet of movement or so. I also drill the jet out to put me at about a 119 jet size that made a huge difference on the top end.

 

[Amarion1]

I really like that set up! That's beautiful

 

[culvercityclassic]

Looks good, and clean.

 

[romerider153]

Thank you guys you all have been very helpful in getting this bike to were I want it. It finally is getting to the point where I can just hop on it and be comfortable knowing it's going to work flawlessly and perform well. Your first predator build is deff a learning experience especially one like this.

 

[romerider153]

Well I'm another rear hub down the imotion3 axle snapped clean. So now I'm not sure what to do try to get another one and hope for the best or just change it to be single speed.

 

[Amarion1]

That's terrible! I hope nothing else was hurt.. Look into the grubee HD axle kit thingymubob. I bought it for my bike but haven't made any progress yet unfortunately =-( but the thing is heavy and seems super solid! I can get you some pics and measurements if you'd like too