Aluminum bike Chainstays block the chain please help

Discussion in '2-Stroke Engines' started by chained, Nov 7, 2014.

  1. chained

    chained New Member

    I have a 29" Genesis GS29 MTB. The bike is aluminum. The chainstays curve in towards the center by design, and they are both getting hit by the chain and prevents it from lining up correctly. I have it now where the chain stays on by bending the tensioner, but it is digging into the frame on both the upper and lower chainstay.

    Is it possible to bend them out a little bit to clear the chain?

    Im afraid that the chain will eventually grind through the frame tubes and cause even more problems. Everything i working great besides this issue. I would like to keep the bike since its larger and a better ride than a 26" bike.

    Thank you

  2. dougsr.874

    dougsr.874 Active Member

    Is it possible???? NO...classic example of motorizing the wrong bike....
  3. Timbone

    Timbone Active Member

    The chain WILL eat through your frame. You must adapt in order to make it work.

    If the frame were steel, yes you could bend it as needed to make a little room for the chainline. But aluminum is more brittle and bending it will lead to premature failure.

    Get some spacers of different widths and start playing around. Maybe you can make it work.
    chained likes this.
  4. wheelbender6

    wheelbender6 Well-Known Member

    The chain tensioner can be used to direct the chain so the the stays don't interfere with it.
    You may even need to run two chain tensioners to avoid chain interference.
    In the pic below, the tensioner directs the chain away from the stay.
    chained likes this.
  5. Robot

    Robot New Member

    Here is a pic of one cut to fit chain

    cut to fit in background but this engine is tack welded to the frame should it be found to help tack only one side of the engine case please..etc etc.

    Attached Files:

  6. chained

    chained New Member

    The chainstay and seatstay both curve in, so no matter how I put the tensioner, it still rubs.
    I notice on the bike above, the rear sprocket is dish side in. Mine is dish side out, but I doubt it would make that much difference.

    Im just gonna try to pick up a used bike locally. If it werent for these tubes interfering with the chain, it would be great. The bike is sturdy and I like the larger size.

    Thanks for the help everyone.
  7. Timbone

    Timbone Active Member

    I wouldn't give up so easily. I had the same problem on my first build. Flip the sprocket to run the chain closer to the spokes. That will make a difference. Then add a spacer or spacers to the left side to push the rear triangle outwards. 3/4"movement may solve your problem.
    chained likes this.
  8. chained

    chained New Member

    I dont want to give up at all. i love this bike. I was going to flip the sprocket around to see how much more space it gives.

    But I am not understanding what you mean by spacers. 3/4" is really all I need, its that close.

    Could you elaborate a little bit on the spacers suggestion? Thanks
  9. chained

    chained New Member

    Im thinking that you mean to put spacers on the hub? If so, thats a good thing to try.

    Sorry, Im new to all this. I apologize for my newbness.
  10. chained

    chained New Member

    Took some pictures, not sure if they give enough reference.

    IMG_20141108_102752.jpg IMG_20141108_102803.jpg IMG_20141108_102815.jpg
  11. Purple Haze

    Purple Haze Active Member

    That looks doable to me. Flip the sprocket, should fix it, if not, judicious use of spacers and washers can work wonders. Once you get enough clearance, use a spring loaded chain tensioner to keep the chain from running sloppy.
    chained likes this.
  12. chained

    chained New Member

    I didnt give up! I think I finally won, with the suggestions that were given here.

    Tried a few combinations of washers and nuts, and ended up using two nuts to push the side out just enough. Its pretty true and rides well. No kinks or noises, and its not hitting the chain at all.

    Heres the pic:


    I had to adjust the brakes but other than that, its all good. The ride is smooth, and the tensioner lines up really well now. Thank you to everyone for the help. Im hoping that pushing that side out wont be any trouble in the future.
  13. Timbone

    Timbone Active Member

    That's what I am talking about!

    Now,you gotta look out for chainslap! If it starts doing damage,maybe you can use something like a thin layer of that fiberglass repair tape to act as a protector.
    chained likes this.
  14. chained

    chained New Member

    I ordered the engine kit from bikeberry. They sent me the 2 bolt tensioner instead of the 4 bolt that was listed. They also forgot the spark plug!
    But I contacted them and they are sending me the 4 bolt, so as soon as I get it Ill put that one on the bottom and the 2 bolt on the top and I think I can take out one of the spacers.

    Gonna flip the sprocket and do all the work at once, when the tensioner gets here tomorrow.

    So far so good.