New member, 1st build in Boston- problems problems

Discussion in 'Introduce Yourself' started by Rhino A, May 16, 2011.

  1. Rhino A

    Rhino A New Member

    Hello all, my name is Ryan located here in Boston MA.

    I have been working hard on my MB for the past couple weeks now, mainly weekends as I bought the bike to commute to work. Where to start, first issue on the build was the chain tensioner. I have read all about the related problems on this forum, so after fixing the rear wheel damage due to it and truing it up I opted for no chain tensioner, which seemed to be a better choice and shortening up the pedal side chain a bit. Now the engine side chain is driving me nuts. Its nice and taught, not too tight though, but seems not to be running true enough to the wheel sprocket. Basically the chain will either get pulled off the wheel sprocket or more recently come off the engine sprocket, finally it broke at a link. I need to pick up some #41 chain for a better fit/ more beefy chain. Basically I've gotten to the point where I don't know how much more to do on my own, I spend hours fine tuning and working on it and I just want the **** chain to stay on so I can move to tuning up the carb and throttle, which are later problems to deal with. I installed the rear wheel sprocket- rubber gasket to spokes to rubber gasket, to try and get it out from the wheel a bit more: one nice thing is I'm not getting any chain rub on the tire. How true does the chain need to be running from the engine to the wheel? Im fairly certain perfection cannot be achieved by the way the engine sits on the bike. Any help is greatly appreciated! PS- any one know where the MA shops are for help, near Boston? My bike is too motored for bike stores to touch it and not motored enough for motorcycle stores to "waste their time".
    Thanks again and its great to be a new member of this forum!

  2. Al.Fisherman

    Al.Fisherman Active Member

    I Ryan, I'm a Bostonian myself...many years ago (Fuller St, Brookline). How I correct the problem might not be what others use, but it works for me. I think we answered the question this thread...
    Last edited: May 16, 2011
  3. BoltsMissing

    BoltsMissing Active Member

    Ok, alot of good suggestions, but here'smy version.

    make sure the engine is mounted good and proper first.

    Put the rear wheel back on with the engine sprocket.
    A tip: Before I place the rubbers onto the wheel/spokes, I smear it plentifull with rubber grease. Thread the bolts through and tighten up every 2nd bolt till it just takes up the slack. So by the time you back to the first bolt, it will be loose again.
    Along the way, with the help of the rubber grease it can be centred and all sorted.

    Put the kit's chain tensionor on, but it is highly reccomended you get rid of the china nuts,bolts and washers. Get quality in that area at least. You'll keep the skin on ya knuckles and save on band-aids!

    When the tensioner is on, put on the chain.
    Look for the lob-sidedness from the engine to the rear wheel, and with a long monkey wrench, twist the chain tensioner so it lines up!
    That's right, twist it a bit.
    It has worked ok on some frames, not on others, but try it out.

    If you could show a pic of the bike, many of us will be able to tell if that option can be done before you do anything first

    All the Best
    Last edited: May 17, 2011
  4. Rhino A

    Rhino A New Member

    Thanks guys for the quick responses, a lot of very helpful tips here. I re-attached the hub sprocket with a lil grease and double checked to make sure it was centered, I was able to have my manufacturer warranty me some heavy duty 415 chain so I am waiting for that in the mail, he said the stock china chain is weak and known to jump side to side. Fisherman: glad to know there are motorbikes in Boston, I think I've spotted 2 since taking up an interest in them, and thanks for the link to the other thread, most of what I've read is leading me to believe I might not have the engine as centered as I thought, and I should make it known I custom made a U-bolt mount for the engine. I'll be sure to take pics and post them up as soon as I can. I have read that it is almost required to twist the chain tensioner to get it to run true with the chain, but after seeing what it could do in the spokes at low speeds I'm thinking I'd rather ride without it. Thanks and again I'll get some pics up here so all can get some visuals going.
  5. rustycase

    rustycase New Member

    Good to hear it's all coming together!
  6. Rhino A

    Rhino A New Member

    Just a quick update on my post, I ordered a manic mechanic hub adapter and 40 tooth sprocket, and centered the engine much better now, thanks again for the quick responses. I'm hoping the new gear will make for a much more stable setup, and I like the idea of hooking up to the hub instead of the spokes. Been a busy past few weeks my apologies for not updating on the fixes sooner. Be sure to let you all know how the ride comes together this weekend and again thanks for the help- glad to be a member of the forum.
  7. Big Red

    Big Red Active Member

    Rhino A,
    The tensionor is also a chain guide. It helps the chain hit the sprocket right and you can adjust the chain tension correctly. I always leave my chain just a little loose to help with sprocket wobble, It's never perfect. also, along with the twist in the bracket, You can bend it in or out to better line up the engine/sprocket connection. But only a little or you'll havs the roller at an angle and the chain wont roll flat on it.
    Big Red.
  8. Rhino A

    Rhino A New Member

    That's a good point on the tensioner, I have read a lot about them on the forum, aside from bending it etc to properly align, do you think its almost necessary to replace the kits tensioner or at least drill a hole through the chain stay as recommended by others to ensure it wont rotate on the chain stay and pull into the wheel? I know when I clamped the weak tensioner that came with the engine kit as tight as possible it still pulled in from the engine torque- I can see where bending it would help this though
  9. Big Red

    Big Red Active Member

    Chain tensioner.

    Hey Rhino A,
    Some frames are thinner at the tensioner connect point which makes it almost impossible to get the stock assembly tight enough. What I do is throw the smaller curved peice in my junk box, take a FLAT peice of good steel, Cut it to size, Drill holes to fit, and clamp it tight. The original peice has a big curve in it and wont allow it to fit tight on some frames. But just to let you know, I'm not the smartest dude in the world so take my advise or not at yer own risk. I will say that this has worked for me on a lot of my builds and altogether I've built about 40 M.B.s
    Big Red.
  10. Rhino A

    Rhino A New Member

    Thanks for the advice Big Red, I'll take it from any one with that much experience, I had an hour to work on the bike last night, mainly putting the 415 chain on and prepping stuff for the weekend, and I believe I've found the reason for my chain constantly derailing. I don't know how my eyes missed this before but the chain is pulling out away from the engine sprocket just a bit to the rear sprocket, IE: the Rear sprocket is too far away from the spokes/ hub. I mounted it sandwich style with rubber on both sides of the spokes but it seems that's not getting a straight enough action for the chain. As I mentioned I do have a manic mechanic hub adapter coming in the mail which should make for easy adjustments but I'm eager to work with the rag joint this weekend. Now I'm thinking a proper re alignment of the motor and getting that rear sprocket closer to the spokes will do the trick, only problem is a chain rub on the tire seems imminent. Is that a common thing? Am I going about this properly?
  11. Big Red

    Big Red Active Member

    Wheel set up.

    Rhino A,
    Hey Ryan, Sounds like your on the right track. If you didnt have the clamshell adapter coming there are a few things you could try. First, pull any extra spacer possible from the right side (peddle side) to get the wheel over a little further. If you have a wider tire than usual sometimes it's the only solution that I've found. Yes, it will slightly "off center" your wheel. You can't really feel any difference in the ride. Then put the spacers on the other side to equal out the hub space.
    Make your own rubber spacers for the rear sprocket. I've made them from an old tire sidewall. You can stack them as much or as little as you need. I DONT recomend puttind ANY metal parts directly to the spokes. It will cut and break your spokes.
    Last, But not least, Make SURE the engine is in straight and tight. Then eyeball the chain straight back to see where it wants to fall. That position is where you want to try to make your sprocket set to. Rubber, spacers,ect, whatever it takes to get it where you need it, SAFELY.
    I dont recomend it but I've done it, AS A LAST RESORT. I've moved the front mount over 1/8" to get the chain to run straight back. I can't remember what type frame it was but everything else I tried was not working. I moved the front mount over perhaps less then 1/8" to line up the chain.
    But all this advice is for naught if the hub adapter works out for you. I've never tried one so let me know how that works out.
    Big Red.
  12. Rhino A

    Rhino A New Member

    Thanks for the tips Big Red, got the sprocket closer in to set the chain right and then noticed my engine wasn't mounted tight enough on the U-mount/lower mount, it was leaning over just a-bit during the test runs and turning the chain up a bit- diagnosed the problem right there, got the hardware (american) down tight and now a good straight chain run from engine to rear sprocket is in place- still running the rag joint but imagine the clamshell adapter will only make things better and more reliable for the long haul when it comes in. Now that I seem to be able to ride I'm curious as to how I should expect the motor to behave. It seems my throttle isn't doing much but it was able to putt me uphill as it wasn't able to before- I'm still getting the idle and air/fuel screws on the CNS carb dialed in and I plan to rewire the CDI wires by twisting them together and wrapping in electrical tape ( I've read on other posts that can often help). So I'm not sure if I just need to be breaking it in now and not expect normal throttle response etc. or should I? Also, my killswitch doesn't work, I'm hoping rewiring will fix it, but the only way to shut down the motor is to come to a stop letting it run itself dead from the drive chain, or on one occasion when the chain popped off I had to physically remove the spark plug cap to get it to stop- I havent heard any alarming increase in RPM's or things of that nature tho. Sorry for the broad array of questions guys but again I appreciate any help in advance!
  13. rustycase

    rustycase New Member

    kill switch

    Rhino, you need to stop everything, now, and focus on one thing...
    It's relatively EZ to run an engine and go fast.
    The basic problem we all encounter is stopping.

    ...and all this is MY personal opinion, so u can take it with a grain of salt.

    Fix the kill switch.
    It could save you, and your engine.

    Then you can proceed with other things.

    ...Like the idle...

    Set your idle speed high... at least it will run.
    Then you can mess with the idle mix, a bit, but the mix adjustment won't work very well, because it is only a strong influence at the lowest idle speeds.

    As you get things dialed in, (make only 1/4 turn, or 1/8th turn adjustments), you can then lower the idle speed to a proper setting. (and then you will need to re-adjust that idle mixture screw AGAIN!)

    Rhino, this is motorcycle advice... OK?
    When dealing with a china engine, your clutch will need to be in very good adjustment, so there is no drag on the motor, that may change with any degree of wear, or actually, change due to everything coming up to temp.
    (I have NO experience yet, with the china engines. Both mine, well, all three, are sitting, awaiting a built frame. Actually, I probably got a dozen china motors around here, for various applications. Basics are all the same.)

    And don't be going up that HILL until you DO get it broken in!

    Rhino, this is ALL my own opinion... someone with more specific knowledge than I may come along with better advice.

    Hey Red !
    Would you tell us more about how you prefer to cut tire sidewalls to make rag joints?

    I've got all kinds of saws, including jig saws, sabre saws, scroll saws and band saws... What do you find to be the best method ? Do you lubricate the cut with water, or mineral oil ?

    I do agree the clamshell hub adapter has got to be the best method, but until I can figger how to build one with the tools I have on hand, and get the stock, I'll need to run a rag joint to 14g spokes.

    (The basketcase I bought had broken spokes and a taco'ed back wheel from the rag joint bolts wearing against the spokes. I replaced spokes, trued the wheel to a 1/16", and it is serviceable. I bought new bolts and nylock nuts to replace those damaged, and must now re-assemble the rag-joint.)

    Next I'm going over to Sheldon Brown to learn how to lace up wheels to hubs... I got some Sturmey-Archer 3 speeds I'd like to lace up to some mtn bike rims so I can see how that works with china power... there's really no definite agreement if they will work, or not... that I have read.


  14. Rhino A

    Rhino A New Member

    Thanks Rusty Case,

    I'm definitely all about safety with these things, reading this forum has inspired me and cautioned me to do a lot: added brakes, take off front fender etc. (of course helmet) I absolutely want the convenience of having that kit included kill switch to work, I'm hoping rewiring will do the trick, but if not, any ideas? I know a lot of guys on the forum go out of pocket for new kill switches first thing, I'd even be looking that route if I cant get this one working.

  15. rustycase

    rustycase New Member

    kill switch

    Rhino, when I was a darn-near-full-time dirtbike rider, we ran a set of automotive ignition points mounted on the handlebars running to the kill switch wire. A guitar pick tied to a string that was looped around our wrist kept the points open, and the engine running.

    If we managed to let the bike 'launch' us, the guitar pick would be pulled from the set of points and kill the motor. Prevented a LOT of 'screaming engine crashes', but NOT crashes!

    I used a 'Kool' leather boot lace...

    S'pose u could consider it anti-theft, if someone did not know what it was...

    Last edited: May 31, 2011
  16. Rhino A

    Rhino A New Member

    Update guys, I want to thank you again for all of your help. I got the Manic Mechanic hub adapter from Pirate Cycles along with one of their custom 40 tooth sprockets in on Saturday and the both slapped onto the rear wheel with ease. The simplicity and design of this thing is a great innovation for motorized bikes and I'd recommend it for every MB built. Pirates sprocket is not only light and durable but looks great and all of the hardware is now securely fastened with American thread via allen wrench. I rewired the electrical following a thread posted by Ducttapedgoat and that solved my killswitch issue and also gave me more power. My upgraded HD 415 chain grips the rear sprocket and engine great and securely runs throughout, I believe things are starting to bond. I went through my speed carb and did everything I could to make sure it would run properly, all functions are now in proper order. I switched out the spark plug for the fresh spare that came with my kit- just in case- I do intend to upgrade to the NGK soon.

    Here's where the Q's come in:

    1. I am nursing my throttle but getting very decent response from the motor, I do notice at WOT it boggs down as mentioned in some other posts, and I have to keep it at about 1/4 to 1/2 throttle to get a good run. I'm still dialing in the air/fuel screw but idle is golden, and of course I've acknowledged that the engine is still in the break in period (2nd tank) So where does the snappy throttle response start kicking in, how do I assure I achieve it?

    2. I air sealed the carb to the manifold with epoxy- is that okay? Its got 20+ mi on it and seems to be holding.

    3. Fuel leaks are messy but not out of control, can I also use the epoxy around the fuel line to seal any leaks?

    4. The chain is running close enough to the tire to where its starting to grab quite a bit of the white off the side of the wheel, tread is still good though, I know I should be alarmed but I really don't see any fix for it, it seems like the chain would rub alot of MB rear wheels- is this something that is common and won't have me replacing tires too often?

    I appreciate it the help!
  17. rustycase

    rustycase New Member

    2. I air sealed the carb to the manifold with epoxy- is that okay? Its got 20+ mi on it and seems to be holding.

    ...This is NOT a good place to use epoxy. Black or red rtv from the auto parts store would be a better choice.

    3. Fuel leaks are messy but not out of control, can I also use the epoxy around the fuel line to seal any leaks?

    ...Also NOT a good choice. It would probably be best to get a better quality fuel line that is nice and flexible and use proper clamps so it seals well at the connection.

    4. The chain is running close enough to the tire to where its starting to grab quite a bit of the white off the side of the wheel, tread is still good though, I know I should be alarmed but I really don't see any fix for it, it seems like the chain would rub alot of MB rear wheels- is this something that is common and won't have me replacing tires too often?

    ...Not only does a chain rubbing on the tire rob you of power applied to the wheel, it could lead to a spectacular failure when you least expect it.
    Elsewhere, someone advised 'dishing' the wheel... Loosening all the spokes on that chain side uniformly, and then tightening all the spokes on the opposite side of the wheel to effectively move the rim over to one side, in relation to the hub.
    I wouldn't advise doing it any more than necessary because it will affect the track of the bike and make it a bit less stable.

    Good luck