Chains Chain rubbing tire

Discussion in 'Transmission / Drivetrain' started by Rhino A, Jun 7, 2011.

  1. Rhino A

    Rhino A New Member

    Sorry if I am bringing up a tired topic but I've searched the forum extensively and can't find any new topics on chain rub.

    Well my problem is just that, the HD 415 chain from the engine is rubbing up on the tire, good enough to chew away at the sidewall and I blew my first back tire 40+ miles into the break in period. Some advice I've heard is to go with a thinner tire, maybe a 26x 1.95. Moving the wheel over somehow? Moving the engine over somehow? The chain isn't rubbing consistently during the run its just close enough to get that slight side to side action and seemingly sand away on the sidewall. I thought I'd start a new thread to collect as much trouble shooting in one location as possible.

    Some more info: I'm running without the chain tensioner- although I'm looking into getting the kip springer tensioner, the chain is taught enough tho, I honestly don't think the tensioner is the answer. Everything runs great minus the simple position of the rear wheel.

    I've also got the manic mechanic hub adapter on there, and its pulled out away from the wheel as much as the coaster brake arm will allow- and getting a good true chain run.

    I've thought of incorporating washers or something similar to get the hub over to the pedal side more, but I wanted to see what the experienced builders would suggest first, keeping the chain run true without rubbing the tire, it seems simple enough but I'm stumped.

    I appreciate any help and excuse me if I've brought up again a thoroughly discussed topic, any links are also greatly appreciated!


  2. tone2crazy

    tone2crazy Member

    i would go with the smaller tire first as it would be the easyist thing. you said go down to a 1.95. what size are you running now? the 1.95 is pretty big.
  3. Rhino A

    Rhino A New Member

    Right now its the stock Micargi tire- 26x2.125, big cruiser style tire
  4. tone2crazy

    tone2crazy Member

    yeah thats pretty big. my 1.95 barely clears the chain.
  5. Rhino A

    Rhino A New Member

    That's good to know it clears tho, I've even seen advertised 1.95 "no chain rub", I know going down from the 2.125 its gotta clear good, does it still ride pretty smooth and handle the roads okay?
  6. retromike3

    retromike3 Member

    Sometimes bigger isn't better

    I have been running 26 by 1.5 with a V pattern for the past two years. They say that there rated for sixty pound but I put eighty in them. They roll really easy I am sure that my milage is a lot better than the 26 2.125 35 psi tires that were on there to begin with.

    With a smaller tire you have to pump them up more often (once a week with these bad boys) on my road bike its every morning. I would not recommend going with anything smaller than a 1.5 unless you have a full suspension bike because, with the added weight of the motor, plus more power your just asking for pinch flats. The ride on a hard tail mountain bike tends to get kind of rough as the tires get smaller.

    When your riding your mountain bike and you hear that buzzing sound when you get to a certain speed . To me that is the sound of energy being wasted. It should be quieter than that.

  7. Rhino A

    Rhino A New Member

    Sounds good to me, I'm going to try out the 1.95 and see how I like it, know any good vendors for tires? Possibly get some white wall? A bit of selection style tread and size etc.
  8. tone2crazy

    tone2crazy Member

    try amazon. my personal favorites are serfas and kenda
  9. motorpsycho

    motorpsycho Active Member

    i don't see how it could have "blown" the tire. bike tires have inner tubes in them and if you let it wear the tire down to the point to where the tube was sticking out, then shame on you. bike tires have pretty thick sidewalls, so for the chain to wear the tire down that fast, it must have really been rubbing on it with a lot of pressure.
    if you knew the chain was rubbing the tire, you should have been keeping a closer eye on it.
    what i would do is to get a thin peice of aluiminum, paint it black and mount it between the tire and the chain. this will make a guard to keep the chain from rubbing on the tire.
  10. Rhino A

    Rhino A New Member

    I think I misworded "blown" the tire, there was no loud noise or dramatic effect, the tire was filled with air, and then quickly it wasn't. I knew the chain was rubbing the tire, had my eye on it, indeed it was a lesson learned but far from a foolish mistake. The tube wasn't sticking out, I just figured tires flat, sidewalls a bit compromised= probable cause. Had to deal with the chain rub until I could get a new tire or mod something up, and I do like the metal piece between the chain and tire advice. Would you advise not to try and mount this to the fender? Or would that be a safe and efficient location. I was able to get a new tire 26x1.95, I'm hoping it helps the problem.
  11. SlugMan

    SlugMan Member

    I run a 2.125 tire and it barely clears the tire, but it does. I use rear axle tugs (axle tensioners) to align and put tension on the wheel/chain, then I can tighten down the axle bolts. It used to take two people to align and tighten the back tire before, but not any more! My chain has not come off since this install. Plus, it did solve my chain rub issue. I don't use the chain tensioner that came with the kit. I don't use one at all... I did purchase a good #415 chain, which helps alot (not much stretch, after several rides).
    Smaller tire would be the answer, but axle tugs will allow you to adjust the rear wheel (left, or right) a little, so maybe it will clear with the bigger tire... They are sold for single speed track bikes and BMX racing.
    Good luck
  12. q999

    q999 Member

    I like my 26x1.75 bell no-mor flats tire setup

    I'm running a bell no-mor flat setup little heavy, hard to install but.. ,clears the chain .no mor flats long it will last?
  13. jroyse

    jroyse Member

    I'm working on the same problem...chain rub that is. So far I have welded 1/4 inch square blocks to the inside of the coaster brake arm, then using longer bolts moved the sprocket outboard 1/4 inch. put the longer bolts thru the sprocket, then run down a nut right against the sprocket, now install the sprocket thru thru the metal plate and rag joint. I figured I would gain 1/4 inch and now clear the tire. Wrong! i got the 1/4 inch but the chain is still to close. I know others have built this type of bike but I've yet to figure out how. The above procedure does help. I should mention the square blocks must be lined up with the flats on the brake arm. This allows you to move the brake arm out and maintain braking. I'll keep after this till I come up with a cure or until somebody replies with one.