Magic Motorcycle/ Coda Magic instructions

Forgot to follow up on this, I've been told by a kindly fellow, bolt toghtening torque is 30 lb-ft (40.7 NM),

bolt tightening torque is 30 lb-ft (40.7 NM)

Click to expand...

That looks a bit high to me :?...360 lb-in. That would be fine for a standard fine threaded steel bolt with a hex head in a steel axle, but the Coda bolt is coarse threaded steel into two aluminium threads.

Also, the 6mm female Allen Kex fitting on the Coda will exert much higher local loads than the bigger 8 and 10mm fittings on current UltraTorque/Hollowtech etc. The bolt could burst open/split at those sorts of torques. It's a lot thinner walled than standard bolt heads, and machined rather than cold forged.

Here's Park's torque guide.

I'd reckon on 150-200 lb-in, 17-20 NMish max...the last thing you want to do is bust the bolt or strip the crank thread.

All the best,

old thread I know, but hopefuly not forgotten..

does anyone know if it's possible to reduce q factor and fine tune the chainline with these MMC cranks ? I have busted out my 96 F3000 for her maiden voyage, and it has one fitted as stock parts, but the chainline is WAY off, and the high q factor has me riding like John Wayne... I need to pull the cranks in a good 10mm :shock: and straighten up the chain aswell... any ideas ?

Other than finding a shorter axle, I don't think so.
You'll need the matching narrower cups, too.

All the best

hm.. thanks.. I feared as much...!

Surely, if the MM/ coda crankset is fitted as stock, the chainline will be ok?
The BB and crankset are matched, so it's not like a shimano square taper setup, where the user can screw it all up by fitting a 127.5mm bb axle on a crankset designed for a 107mm bb. This system was made for a 73mm shell or a 68mm shell, and that's it. Offchance, a 73mm setup could be on your 68mm cannondale, shell but back to my original observation, it it's stock, why would cannondale have done that?
Not to say you haven't done something correctly, but you haven't bottomed the bolts before the arm is all the way on have you? When torqued, the head of the bolt should be flush with the counterbore on the crank arm. if it's protruding, chances are the bolt is bottomed on the arm, and not up tight at all on the axle.
Any chance of posting some pics so we can help?

indeed, I will have a look at that and let you know, it could well be something to do with those strange crank bolts... I can't help but think why they designed them like that...?! when a standard M8 would have done the job.. :facepalm:

what's the clearance like on your frame?

If you are looking for the "Real" magic motorcycle instructions look on this link..
http://patineto.smugmug.com/Bicycles/Co ... ;k=TfHgwkJ




I hope this helps..

thanks for the instructions I will have a good nose when I get the chance,

I did check the bolts and installed the arms correctly, the chain stay clearance at the pedal is 13mm on both sides, and about the same between outer ring and chainstay, way too much!!

Crank arm to chainstay distance is irrelevant. This is a wide Q crank and frame design as well as crank design will affect this distance. Chainline is what will dictate correct position, so when the centre of the cassette lines up with the centre of the middle ring. As it's a "normal" symmetric production frame (nothing odd and asymmetric and on a 140mm rear axle for example), measuring the centre of the middle ring to the centre of the seat tube is enough of a datum to judge alignment on.
Shelon can help rather than repeat what the good man has documented already.
http://sheldonbrown.com/chainline.html