I need a wider pedal crank...

[RedBaronX]

after dry-fitting my motor with exhaust to my frame, the pedals won't clear the exhaust.... I'm going to assume the better solution is to get a wider-spread crank that accommodates the exhaust instead of beating the exhaust into submission... Any suggestions what set to buy?

I have a Greenline beach cruiser, and the specs say that they are 6.7".

 

[GearNut]

The common cure is to gently and lovingly bend the exhaust into submission.
Use a MAPP gas torch or oxy-acetylene torch to make things easier.
Don't put a kink in it though.
Many small bends are better that one big bend.

 

[Chalo]

If you have a cruiser type bike with one-piece cranks (which are awesome by the way; don't get me wrong), then you'll need a special wide 1-pc crank:

http://www.bicycle-engines.com/wide-crank-pedal-p-106.html

But if your bike has a threaded bottom bracket, you'll need a long spindle bottom bracket such as that sold by Sickbikeparts:

http://www.sickbikeparts.com/catalo...ucts_id=114&osCsid=4i1i1r3o1f8utimcahouahmbq3

I think it's a much better idea to make your engine fit the bike than to make your bike fit the engine.

Chalo

 

[RedBaronX]

The common cure is to gently and lovingly bend the exhaust into submission.
Use a MAPP gas torch or oxy-acetylene torch to make things easier.
Don't put a kink in it though.
Many small bends are better that one big bend.

I'd definitely rather bend it than spend more money because bending it is free. I don't have a torch, but I won't have to bend it that much. The crank rubs the muffler.... I'm just using the short pipe stock exhaust, so there is not enough pipe for "many small bends"

 

[RedBaronX]

awww SWEET... there is a vintage motorcycle shop stupidly close to my house that I didn't know about until about ten minutes ago... it's three blocks away. I'm sure they will be able to bend it for me. I'll get the rest of the bike ready and then just roll over there on my next day off. means I also have a REALLY handy place to pick up 2-stroke oil!

 

[Outa_Spaceman]

I had a very similar problem when fitting my Gen II engine.
Both the muffler and the pedals fouled the engine
I over came it by extending the rear engine mounting studs thus allowing the engine to be mounted higher up the frame.
All seems well with both problems solved in one fell swoop.
Here's a link to my eureka moment:
http://outaspaceman.blogspot.com/2011/01/sundry-mortifications-no17-another-year.html

 

[DuctTapedGoat]

I run 3pc cranks, and just swapped over a wider crank arm. You don't need a whole new assy, just new arms that come out further.

I had to so I could dodge the magneto and clutch covers, but it reduced how far I had to bend the exhaust.

 

[Max-M]

DuctTapedGoat:

I'm building a MB using a Giant "Simple Single" cruiser, and it has a 3-piece, alloy crankset. I need to extend the crank arms outward to clear the engine and Q-Matic drive.

Where did you find your wider crank arms?

Thanks,

Max

 

[DuctTapedGoat]

I didn't have to go beyond a gearbox, just the basic 2 cycle block. I ended up stealing the left crank arm off my stumpjumper, which was just perfect.

 

[Chalo]

Wide bottom brackets

(The bottom bracket is the component that includes the crank axle and bearings.)

Wide bottom brackets for three-piece cranks can be found at Sick Bike Parts. They are very nice units; I've ordered one for a customer at my shop before.

http://www.sickbikeparts.com/catalog/product_info.php?cPath=23&products_id=107

SBP has them in three lengths. To preserve your ability to pedal, use the shortest one that has enough clearance for your motor-related equipment.

Chalo