Bicycle Mechanics - Removing odd size crank from older low-end MTB:

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Medic Zero
09-04-11, 12:05 AM
Like the title says. I picked up an old '91 Sekai "Mountaineer SL" MTB (AFAIK same as Norco) to serve as a back-up to my '88 GT for commuting duties. It is totally OEM equipment, been literally sitting in a garage for the past 20 years. When I went to pull the cranks I was stymied by my Park tool not threading (worked just fine on my Timberline a few minutes later). Looking at it, there is what appears to be a 14mm nut in there but doesn't appear to have any clearance to actually get a socket around it.
Is there another type of crank puller tool I need to purchase?
This has not only a 20 year old components but it appears to be super low end as well. Ultimately the frame itself suits my needs and I was able to roll home on it after purchasing it, so I'm basically happy with it in the long run, but stuck for the moment. I was hoping it'd be fine for about a week or so to get to work and back while I am waiting for parts to come in (and time to install them) for my main bike. Unfortunately, after less than 50 miles I am starting to feel some play in the cranks, noise at times (clicking-ish), and noticing some grease escaping onto them, and so am afraid I need to figure out getting those cranks off sooner rather than later. :/
I'll upload a photo in the morning, I'm posting this during my overnight shift at work, but I figured some folks here would be able to help me out even without the photo.
Dan Burkhart
09-04-11, 12:42 AM
I'm guessing you have part of the plastic dust cover still stuck in the puller threads.
Medic Zero
09-04-11, 05:53 AM
I don't think so. I'll double check, but I initially tried on both sides, same result (not threading) and one of the dust covers came off quite cleanly. There was a little bit of plastic on one side, but I removed it and tried again still no luck. I don't have a thread chaser, any recommendations for something else to use to double check that they are free of obstruction?
I assumed since the cranks are kind of funky looking, REALLY cheap looking, and a fairly early era mountain bike that maybe they were some oddball size.
You need a thin wall socket to remove the nut, then use the crank arm puller. Most likely the end of the spindle is a threaded stud. Not uncommon on lower end stuff.
http://www.bikepartsplace.com/images/med/31681472.jpg
HillRider
09-04-11, 07:51 AM
This may be a "nutted" spindle with threaded stubs at both ends and they could keep the puller from seating. Try backing off the center screw press all the way and see it it will thread in.
Medic Zero
09-04-11, 07:07 PM
This may be a "nutted" spindle with threaded stubs at both ends and they could keep the puller from seating. Try backing off the center screw press all the way and see it it will thread in.
I backed it WAY off, but it's possible I might have been able to back it off more. I'll try that one more time, but am thinking I may need to track down a thin wall socket. Anyone know if I am correct in assuming that is a 14mm? Also still open to suggestions to clean out any possible lingering plastic in the threads (sans threadchaser).
Thanks everyone!
Medic Zero
09-04-11, 07:08 PM
You need a thin wall socket to remove the nut, then use the crank arm puller. Most likely the end of the spindle is a threaded stud. Not uncommon on lower end stuff.
http://www.bikepartsplace.com/images/med/31681472.jpg
I suspect you are correct! Thanks!
HillRider
09-04-11, 08:21 PM
I backed it WAY off, but it's possible I might have been able to back it off more. I'll try that one more time, but am thinking I may need to track down a thin wall socket. Anyone know if I am correct in assuming that is a 14mm? Also still open to suggestions to clean out any possible lingering plastic in the threads (sans threadchaser).
If the nut is still in there no puller is ever going to fit. A thin wall 14 mm is the most likely size. There were a few 15 mm nuts/bolts but 14 was more common.
Preynmantis
09-04-11, 10:03 PM
If the nut is still in there no puller is ever going to fit. A thin wall 14 mm is the most likely size. There were a few 15 mm nuts/bolts but 14 was more common.
+1
However, most good quality (Craftsman) sockets will fit on them. They look like they'd be too close, but they fit. I haven't found one yet that my set won't fit.
I backed it WAY off, but it's possible I might have been able to back it off more. I'll try that one more time, but am thinking I may need to track down a thin wall socket. Anyone know if I am correct in assuming that is a 14mm? Also still open to suggestions to clean out any possible lingering plastic in the threads (sans threadchaser).
Thanks everyone!
You HAVE to remove the nut FIRST or all you are going to do is strip the threads out of the crank if you get the puller on without removing the nut. +1 on the 14mm craftsman 12 point 3/8 drive usually fitting
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