Chains 410 vs 415 drive chain, catasrophic failure brand new engine

Discussion in 'Transmission / Drivetrain' started by hms-one, Mar 4, 2010.

  1. hms-one

    hms-one New Member

    I bought My engine kit from a site called It is a 66cc grubee skyhawk GT-5. The kit came with a 410 bike chain. My second trip I ran into problems with the chain jumping the drive sprocket and mangling the chain and damaging inside of the clutch arm cover. I cleaned up the damage to the cover with a buffing pad, Fixed & lubed the chain, going link by link to be sure they were bending w/o seizing, and adjusted my sprocket alignment with some washers at the back wheel. Everything seemed fine for the next two trips, but on my third trip since the fix, the chain jumped the drive sprocket again, this time breaking the cover off of the engine and taking the outer bolt hole off with it.

    The guy at piston bikes is refusing to send me the parts to fix this persuant to their "30 day parts" warranty based on "user error". In other words , I fuxed it up. He said that this was caused by bad sprocket alignment. He recommended that I buy a whole new engine(from him of course) and keep this one for parts. This is not an alignment issue.

    It's a Brand New Engine! It engine barely has 10 Miles on it. I have built 2 kits before, and both came with 415 bike chains. I have NEVER had a problem with the chain jumping the Drive Sprocket. I bought the Grubee because I read that they were considered the best quality(as far as that goes.)

    Has anyone out there had similar issues with 410 bike chains, and/or skyhawk kits? Do skyhawk kits come with a 410 chain standard, or did these guys sell me sub-standard parts? Any advice would be greatly appreciated.

    Attatched are some pictures if my engine and alignment that I also sent to

    Attached Files:

    Last edited: Mar 4, 2010

  2. Gh0stRider

    Gh0stRider New Member

    I have had the chain jump and lock up the rear tire when it gets bunched up under that cover. Once I adjusted the chain tension properly the problem went away permanently. Too much slack and whammo, skid marks on the road and in your pants!
  3. Gh0stRider

    Gh0stRider New Member

    Luckily, I did not sustain the damage that you did but I had to remove the gear to free up the chain. Bad design.
  4. MotoMagz

    MotoMagz Member

    Hms,wish I knew about the 410 chain...someone will be able to help you.You need to go to Vendor Reviews and write a review. A company big or small should do what they can to help....not try to sell you a new engine,thats bs.This is not your first build.

  5. biketec

    biketec Member

    Or just send you the parts you need to fix it!! Oh wait they dont have the right parts! Or parts at all for that matter!
    there's about 4 sites out there I will not mention names but all owned by one person because the other went out if you look closely at design and color schemes and possibly the same happy *** face with a head set on waiting ever so patiently to take your calls or a guy in a lab coat checking a 200000 sqft warehouse and his clipboard inventorying his fake non existent inventory, there called stock photos and any O.S. commerce has them for people with no skill .... that would be them besides anyone who wants to turn the MB world into Mcdonalds and serve a billion double dukies is... well not good for our cause.... Speaking of just seen a commercial for a motor kit on Comedy central the other night BLA! :ack2: sorry about that I may need to edit just venting but it is BS because vendors in the industry for 5+ years no names :whistling: would be more than willing to help you out and sure you pay a bit more but it is what it is I guess again sorry for the rant.
  6. hms-one

    hms-one New Member

    what I thik happened...

    was that The narrow chain had enuf room to pop off the teeth and get wedged between the sprocket and the clutch arm cover. I never dropped a chain off the drive sprocket when I was using a 415 chain. The wheel sprocket, yes, but not the drive sprocket.

    Also this site will not let me write a vendor review for an unlisted vendor until I have made 30 posts. If I had checked the vendor reviews before my purchase, I would have taken the lack of any pistonbikes listing as a bad sign.

    Thirdly, the site has a BBB Accredited business JPG on their page, but when I look them up on the BBB website, Anthony Lee Inc.(same name and phone as on pb website but different address) lists the web address of a childrens golf supply website, and is listed as a supplier of kids golf accesories. I am ****ed and I am thinking of contesting the visa charge If he remains unhelpful.
    Last edited: Mar 4, 2010
  7. AussieSteve

    AussieSteve Active Member

    hms-one, this is a very common problem and happens with both #410 and #415 chain, usually, as GhOstRider points out, when the chain has slack in it.

    Many here recommend #410 chain and say that it works better.
    I found that it doesn't seat properly on the countershaft sprocket, (of my bike).
    The teeth are slightly too wide for the #410 chain. Aside from that, I think that 410 is a better choice, so I'm grinding the sprocket slightly to suit the #410.
    The countershaft sprockets appear to all be poorly-machined rubbish, with no consistency.

    Too late for you, of course. Follow up with, but don't expect too much.
    As mentioned, they operate under several names and have a terrible reputation amongst some people here.
    Last edited: Mar 4, 2010
  8. Fabian

    Fabian Well-Known Member

    This is how i've solved chain tension problems, on both sides of the engine.

    It's worked to perfection.


    Attached Files:

  9. AussieSteve

    AussieSteve Active Member

    You've done a good job on those tensioners. Someone mentioned it the other day. They're having trouble with the RHS chain.
    Touch wood, but I've been lucky. I had to re-tension the RHS chain a few times initially and now it's settled well. It's stayed tight for over 100km. I did a 20km ride yesterday, giving it a fair bit even with the MegaRange 1st gear and the RHS chain didn't loosen at all.
    The LHS chain is no problem, except that it hates the countershaft sprocket and won't seat properly. #410 and a sprocket grind will fix that. No worries with the jackshaft sprocket. It'll love the #410.
    It's only noticeable when turning the pedals slowly by hand, on the stand. A notchy feel, as the chain goes over the countershaft sprocket, if you know what I mean. It's just an indicator that things aren't as good as they should be. Everything else runs smoothly.
  10. Fabian

    Fabian Well-Known Member

    Something else needs to be added to the 415 chain debate.

    From what i understand, there are two variants of 415 chain - "metric" 415 and "imperial" 415

    I don't know which one has the correct pitch for the Chinese 10 tooth sprocket.

    I've experienced this problem myself.
    I'm not sure if 415 chain was supplied with the SickBikeparts Deluxe Shift kit, but i do remember that i had 415 chain from the original Chinese pushbike engine kit and i had another chain from somewhere else.

    The first 15 outer link 415 chain fitted the 10T and the 17T jackshaft sprocket perfectly, but when changing to a new 415 chain, the links would not fit around the 10T engine output shaft sprocket.
    It was like the pitch was slightly less than 1/2 inch.

    I'm confident that the original 415 chain supplied with the Chinese engine kit did not fit correctly.

    Last edited: Mar 5, 2010
  11. hms-one

    hms-one New Member

    side by side..

    the "410" bike chain I was sent (on the left in the picture) doesn't really seem much bigger than a standard bike chain (on the right.) Also, here are shots that show damage to the outside of where the chain normally runs on the sprocket. I was running without a tensioner, but my chain was good and tight with room to tighten by moving back in the forks as the chain stretched.

    Attached Files:

    Last edited: Mar 5, 2010
  12. AussieSteve

    AussieSteve Active Member

    Are you sure that your wheel doesn't move slightly forward or that there isn't too much tightening/loosening as the wheel turns?

    #410 is only a little wider than a normal bike chain, nowhere as wide as #415.
    Does the #410 fit snugly on the countershaft sprocket, without binding on the sides of the teeth?

    That chain looks to be very poorly made - on the LHS of the pic, there's a gap between the end of the rollers and the side-plates with some links, like it wasn't pressed together well during manufacture.
    That might allow it to move side-to-side more than it should and jump the sprocket.
    Last edited: Mar 5, 2010
  13. hms-one

    hms-one New Member

    that's the chain I got with the kit, and I would agree that it is poorly made. My chain tension was good, and the chain seemed to fit well, but even just walking the bike I would sometimes hear the chain 'pop'. I thought I had fixed that after the first time my chain got caught & mangled.

    How does the chain in the picture compare to chains that y'all have gotten with your grubee kits?
  14. cigron

    cigron Member

    After braking a 410 chain twice not at the master link. I went
    to tractor supply and bought number 41 chain. that was the end of that
    problem.That chain out lasted the motor.
  15. mike93082

    mike93082 New Member

    You know I had the issue with two chains breaking and the chain popping off. I read some people who suggested #41 chain. I went out and bought some tonight and I must say yes it is way overkill duty wise. But the chain itself fits very nicely over the sprocket and it is wide enough that it looks like it will be somewhat forgiving as far as jumping off the teeth with the width.
  16. I had an issue much like yours. My chain would pop and pop off, even when just pushing the bike around. I found two things. I have a coaster brake and the chain was hitting the bolt that held the end of the coaster arm. I moved the arm more and it stopped popping off. As for the noise that it was making, I noticed several tight joints in the chain. As it would wrap around the big sprocket, you could see the links that were tight and wouldn't allow it to seat totally on the sprocket. I lubed the chain and it all went away. But, I also went to Wal-Mart and bought a new chain from Bell. It took two packs of the chain but, it's been running fine now and I've got over 750 miles on the bike. I would say to check your chain for those issues and, of course, make sure that your sprocket is straight and, isn't too far out of round as the wheel spins. that'll make it impossible to keep tight.
  17. Chris Crew

    Chris Crew Member

    I have not had the chain problem--but I have had the Pistonbikes problem. Sold me two leaky tanks and didn't care enough to even try to do something about it.
  18. happycheapskate

    happycheapskate Active Member

    Exactly! re: post #11
    first photo on left of chain with big gappy links. This is the one I got!

    The rear cog is too wide for a standard narrow BMX chain (the bell walmart gold chain) but should be fine with a wide bmx chain like for half pipe/grinding bikes.

    Check out for low prices on chains and 26"xdecimal tires like the Swiss Army Knife or the Cheng Shins.

    Purchase an appropriate heavy duty chain and heavy wear tires and save a headache.

    Oh wow this is a good topic. I bought a 48cc Grubee Skyhawk 2009. The first few rides, I had problems with the chain jumping the rear cog. This went away quickly after soaking the chain in motor oil, then greasing it a little.

    The chain looks like a BMX chain, but a little wider, where the rollers can wiggle on the links a little. But it must not be a "415 chain" because I ordered a half link for that and it was HUGE compared to the chain I'm running.

    I resolve to just throw away the factory chain on any kit and buy a good quality garage door chain or wide BMX chain to start with.
    Last edited: Mar 11, 2010
  19. happycheapskate

    happycheapskate Active Member

  20. sajoe

    sajoe New Member

    I too had chain problems and went to Tractor Supply and got the #41 chain. Then I took it one step further. I got rid of the tensioner. I made two adjusters and brackets and I have not had to adjust my chain in almost 1 year. I have attached some pics to show what I mean.

    Attached Files: