Cranbrook which way to put gear on

Discussion in 'Frame Mounted Engines' started by raattlerviper, May 2, 2010.

  1. raattlerviper

    raattlerviper New Member

    Ok I bought a cranbrook and assembled it today. Putting a few miles on it before I engine on this Thursday. Engine is a 60cc chinagirl 2 stroke frame mount. The rear cog is dished and can go on 2 ways for alighnment with the engine cog. Now since it is such a popular bike to slap a engine on which way is the proper way for this bike so it lines up right the first time?

    Thanks guys

  2. I have a Grubee kit with the 410 chain and I put the rear sprocket with the dish facing the wheel (teeth closer to the tire) and this gave me the most clearance for the chain and the frame. I do get a little rubbing of the tire and the chain once in a while. But, it doesn't click on the frame. If you have the bigger 415 chain, this may or may not work for you.
  3. Al.Fisherman

    Al.Fisherman Active Member

    I have a Huffy Cranbrook and which was the first cruiser I built. I mounted the engine with the supplied parts which is NOT the way to do it, but can be done. To alleviate both the tire rub (dish in) and the frame rub (dish out) which can happen using factory instructions, here is a good fix. This mount can be made easily if you have the equipment, or if someone you know does. I can also make one and ship. Other types can be bought from vendors...DON'T drill the frame. Mount the engine a little higher up on the frame tubes. This will do two things...the sprocket can be mounted dish out away from the tire, and secondly the chain will ride at a different angle and away from the frame. What I like with the mount I made (3 of them so far) is that it enables the engine to be mounted correctly. The angle of the mounts to the tubes should be of this...take two correct diameter short pieces (say 1 foot) of tubing or pipe and bolt the engine to them as they would sit in the frame. Now the angle the two pipes make is the correct mount to tube instillation. You can't get this good of a fit from almost all bikes... The angle is 75 degrees. I'd say anything other then 75 degrees + or - 5 degrees would be best to add a customized front mount. With proper fit this allows you to torque the engine mount, secure engine and without over torque. I torque 6mm hardware in aluminum to 50 inch pounds. This is not tight enough to keep the engine from rotating (engine torque) on the tubes so I made a small "L" bracket that bolts to the clutch cover and bumps the frame. Before you do ANY kind of mounting change ALL the studs from the Chinese junk (about a grade 3) to a grade 8.8 (US grade 5). Notice how the chain is routed up and away from the frame, also the correct carburetor bowl angle.

    Make sure the wheels are tuned...turn bile over, spin wheels looking for any wobble in the tire/wheel. This is the time to tune (adjusting tension on spokes)the wheel. I remove the tires to tune the wheels. Remember then working with tighten them, never loosen them to achieve alignment. The angle iron used on this front mount (between the arrows) is a 1-1/2" rise.

    Attached Files:

    Last edited: May 2, 2010
  4. BAM

    BAM Member

    mine is dished out shinie side in 1300 miles . No problems with chain ever it took me a long time to get rear sproket right . had to get all bolts started and slowly tigheten bolts chirs cross spin wheel look for wooble . I think the hardest of build was sproket good luck with yours Have had to tighten chain alot though!
  5. Al.Fisherman

    Al.Fisherman Active Member

    I took the dust cap off (for measurement) and enlarged the sprocket hole so as to have a near perfect fit. Bolted right on without any problem. I have a vid on U tube about how I did it. I chose not to cut the lip off of the dust cap. Although there are those that say they don't have a problem with dirt, I felt it was better no to cut it off. That's me.
    Last edited: May 2, 2010
  6. KCvale

    KCvale Motorized Bicycle Vendor

    My 1st was the Huffy Cranbrook as well, with a 48cc Grubee motor kit.
    I mounted the dish out with the shiny side over the hub and flat against the spokes, then only used the big thick mounting ring on the retention and nut side.


    It has about 350 miles on it and 2 problem drive train or wheel problems.
  7. raattlerviper

    raattlerviper New Member

    Thank you guys so much. It is gonna be a #41 chain (supposed to arrive thursday) and I have a no drill mount that I purchased. If the motor doesn't sit right I will have my buddy break out the angle iron and make me a mount extesion. You guys gave me tons of ideas on how to mount it and tips and I feel more comfrotable tackling the job now.

    Build is scheduled for Thursday and Friday of this week. Looking forward to gettin the engine on and giving it the first test ride. Most important thing to me is doin it right the first time.

    Once again thank you guys.
  8. arkives1

    arkives1 Member

    Ron gave good advice and information (as always!) My first build was also a Cranbrook. My mount is almost identical to Ron's and it works beautifully. I also machined out the hole to fit the hub almost precisely and it runs true. The weak link in these set ups is always the tensioner although mine has stayed put I have heard horror stories. I too put the concave side out and had no issues with chain rub. The higher engine placement also allowed me to adjust the chain so that only a short tensioner was needed (at it's lowest wheel placement) which might reduce the leverage the chain has to pull it inward. I have pull start and centrifugal clutch on mine which further reduces the jerking of the chain. Not a bad bike for a first build but I find it had a pretty hard ride compared to my other cruisers. I hope you have a great build and enjoy the ride as we all do.
  9. KCvale

    KCvale Motorized Bicycle Vendor

    Must be different kits. I pulled off the dust cover on the hub and my sprocket fit it perefctly. I even had room to put the dust cover back on before the locking nut.

    I suggest you try the tensioner on the pedal side as well, if you need it at all.
    I have a topic here about "The Half Link" that may make it so you don't need a tentioner at all.
  10. Al.Fisherman

    Al.Fisherman Active Member

    A way to get around this (actually a little extra security) is to drill a hole in the bracket (facing it) and tap the either a standard thread or a metric thread. Use either a short bolt or a set screw, when in place tighten the bolt/set screw jamming it to the frame. Just have the fastener long enough so that a couple of threads are exposed, ensuring only threads are in the hole taped.
  11. raattlerviper

    raattlerviper New Member

    I actually read your post about the halflink...and when I ordered the #41 chain I ordered 2 masterlinks and 4 halflinks so that I hopefully would not need the stupid tensioner. To me they look like a afterthought to try to figure out how to get the chain taught.
  12. I think the tensioner is included so if you dont have a chain breaker,hacksaw or powersaw,hammer and punch, or if you just dont know how to shorten a chain.