Adapting Non-Schwinn crankset to Lil' Chik

[Dr. Tankenstein]

Hoping I can get some insight into a crankset swap I'm doing on my daughter's Lil' Chik.

Long story short, the crank was rubbing the AWESOME graphics on the chainguard. So, member Jpromo hooked me up (THANKS DUDE!) with a Murray crank that will fix the problem.

Thing is, Schwinn used 28 tpi on their cranks or maybe it was 24 tpi, either way, it's different from the Murray. So, from the parts bin , I've sourced the bearing races, bearings and jamb nut.

I put it together and it spins 'OK', but when I put the chain back on.....ugh, not so good. It feels like the chainline is off, yet the spacing didn't change.......hmmmm

Do I need to replace the bearing cups too? If everything spins OK, I'm not sure why I would.
should i try flipping the rear sprocket (running a Nexus 3 speed coaster)


Thanks for the help.

Cheers,
Dr. T

 

[CRASH]

tpi? Not familiar with that.


Can you put a spacer in around the chain ring to adjust the chain line? You'll be able to look down the chain to see which way it needs to go.

 

[OneHorsePower]

yeah try flipping the front sprocket first , if not enough flip the rear one also ,
the spacer behind the sprocket side race also work ,just have to check how much threads you have left on the lock nut side,
but the thing with spacers is it will offset the hole crank

 

[deorman]

Although they fit the same bracket, some Schwinn outer races are not compatible with standard bearings. There are also different depths that work with different shaft spacing. If your Schwinn had cone-shaped inner races it shouldn't be a problem, other than the axle spacing issues already mentioned. If your inner races were 1/4 round, it may be an issue.

 

[Dr. Tankenstein]

Sorry, tpi=Threads Per Inch.

The Schwinn bearings were definitely too small for the new races, pulled a set from my 56 Murray-built Higgins, they fit perfectly.
The bearings fit just fine in the Schwinn cups, but I used a LOT of grease, so it's hard to tell how well they set in them, ya know?

Like I said, without the chain on, it spins OK, not great, but OK (could be cranked down a little too tight, I'll miss with it)

I'm gonna remove the chainguard and flip it over tonight to check the chainline and see if I can find the bind. The chainring is dished slightly, so i could flip it, just need to polish the backside if I do. If chainring/sprocket flipping doesn't do the trick I'll look into shimming. I think there's enough threads on the non-drive side to handle the spacing.

Wish me luck!

 

[user 135]

A tight chain will create that problem more so than chain line. I would still try to get a matching BB. http://www.amazon.com/Wald-Bottom-Brack ... B003UPZLI8

 

[B607]

Why don't you just use the original parts and put a washer under the stationary cone that holds the chainring to the crank. That will set your crank out a bit and save the paint job. It might throw the chain line off, but might not. Matching generic parts to a Schwinn...no fun. Gary

 

[Dr. Tankenstein]

Both good ideas, I need to put this on a shelf for a few days, but I'll look into both options.

Cheers,
Dr. T

 

[Dr. Tankenstein]

OK, this is a little embarrassing, the rub/bind was due to the chain hitting the fender....... :roll:

Flipped the chainring, and we're good (glad I did because the chain line was a little geeked anyway).

Guys,
As ALWAYS, thanks for your insight and advice, long live RRB!

Cheers,
Dr. T