i would sell my set but I just don't think it would work out well for etiher of us. If you had a black Miche/Omnium/75 set, i would trade. But, if I sell you my silver set for a fair price, then I won't have enough money to buy a brand new black set. O well.

Hey, in the future you should try self-extracting crank bolts. Don't know much about them, but they could help.

Yeah, getting it off the bb without further damage could be tricky. If you can get the drive side cup out, great, but that's a PITA even when the bb is out. If you can find a shop locally with the thread repair tool, it should be possible to tap it in place without removing the bb. Or if the tool isn't available locally, maybe another shop would loan it out? Seems safer to ship the tool than trying to disassemble so you can ship the crank arm.

You're right.

I just called ben's cycle where I bought the cranks from and they busted their asses to help me out.

Sending me a new 75 crank arm set in silver for $100.

I mean, it's $100 down the drain, but what else can I do.

I just need to figure out how to pull this without damaging my bb/spindle.

A gear puller might do it, if it will fit between.

https://www.google.com/products?hl=en&q=gear+puller+tool
https://search.harborfreight.com/cpis...keyword=puller

Stick a coin, or washer in there to protect the end of the spindle.

That's awesome, sounds like Ben's is treating you well. They probably just need to cover some of their cost by charging you $100. Sell the non-drive side arm on Ebay. There could be someone out there willing to pay like $50 for it...

Also, you're not going to damage your BB spindle. It is made of hardened steel while the crankarm is made of aluminum. The crank arm will hollow out long before the spindle gets rounded.

Oh wait... drive side may need bigger jaws.

I hope this thread doesn't make people doubt their 75s or future 75 purchases. I've been riding mine for 3 years with a few rebuilds and the threads are like new.

The force needed to strip the threads all the way from the bottom would seem to me quite great. Crank threads and BB shell threads are one of those areas of bicycle repair I am quite careful with... especially since I only learn from mistakes

Good luck OP, I suggest you don't waist your time with a warranty. The cranks are still usable, just takes longer to rebuild the BB.

I guess I'll find out this winter when I pull mine for the first time.

Yea, well I've got a new set in the mail; I'm not turned off by the quality of the arms, but the whole situation makes me wish all of our track parts were American made.

I have the 3 jaw balancer puller, a tie rod end fork, and if worse comes to worse, an angle grinder to get off the old arm. We'll see how it goes when I get home from work.

I call BS/user error.
I have never seen this happen and I really don't understand how it can.

hey now, that makes no sense at all!

Hmmm. Would you have the same opinion if the product were not Japanese?

Agreed.


Thread failure is evidence of user negligence. It is your responsibility to make sure extractor nut is properly resting on cranks’ base before proceeding to extract. I know sometimes you have metal shavings (or rock granules for that matter) that can get it stuck tricking you into believing is fully engaged.
When you fail to do so, sharing force are then exerted or transferred to the threads which are not in any way designed to support this load.

Pretty quick on the race card there, slick.

wtokyo I'm not convinced you're very experienced working on bikes if you've never seen this happen. I am confused on how you don't understand how extraction threads could be stripped. It seems pretty straightforward? Puller in, torque out, threads yanked. Not too confusing.

This set of cranks was brand new on a brand new SG75 bb. The crank puller is my trusty park ccp-2. Naturally, none of you have met me or know who I am, so you'll be the first to claim user negligence. There was no grit inside the crank preventing the puller from seating all the way, nor a hiding washer. The tapers were greased before I installed the arm, and I even lightly greased the puller threads. Bottom line is the crank arm was seated on the spindle with more torque than the aluminum extraction threads could handle, and the steel puller bit them off on the way up.

I'll be the first to admit when I'm wrong, but this was one of those rare occurrences that cost me money, and not necessarily any new knowledge on the R&R of square taper cranks.

Gee, I didn't know that Japanese was a race. Gosh, I must have been ignorant to think it was a nationality.

Has nothing to do with country of origin. My opinion is based on this particular manufacturer and my first hand experience with their track specific cranks: Mighty/Super Mighty/Aero Mighty/75/Grand Mighty. None of these have shown that kind of failure.

Yo!:
If it is like you say it is, please do all of us here a favor and take this up with the manufacturer and not a retailer. Maybe there was defective batch that got sent out and Sugino needs to know.

How in the world am I supposed to get in touch with Sugino? I mentioned how I wish there were more American track parts in a previous post in this thread for exactly that reason; I would be able to communicate with the company to see what's up in the event of a failure.

I called my friends at the LBS, and they have no contact past a distributor, so it would be impossible for me to be in touch with anybody at Sugino in Japan; the language barrier would also prohibit me from accomplishing anything, and a distributor can't pull the trigger on what constitutes a faulty crankset.

If there is a Sugino USA or a warranty dept. stateside, I'd contact them right away. But when I called and told Ben's cycle my dilemma, they offered me up a new set for $100 as a make good, and I have a new set of arms in the mail today. Probably a lot less of a headache than tracking down an english speaking Sugino warranty rep.

I don't believe Sugino makes bad products, which is why I went with another set of 75's, even after this scenario.

Believe it or not people in companies with a large export market speak English. Hell, I've even called Cateye in Japan and spoke to them in English.

Maybe give them a call?

https://www.suginoltd.co.jp/english/c...e_english.html

Have you ever considered one of these? >>>> https://www.paulcomp.com/rdcrank.html

Think I can borrow your phone for that?

Tejano, I actually spoke to a guy on Sunday ab those Paul cranks and I heard they're really spindly because of the thin spider. You ever tried them out?

This response is evidence of reading negligence. He clearly stated earlier that the crank arm was stripped smooth all the way down to the base of the extractor threads. Taking what the OP has said at face value, he used the extractor correctly and the threads gave out. This clearly isn't a common occurrence, and the vast majority of stripped threads result from user negligence, but why is it so inconceivable that the threads on a single 75 arm were faulty? Even the tightest manufacturing practices have some non-zero failure rate.

Yo!
Did you get the crank arm off yet? On my last crankset that I took off the threads were too damaged to even thread the crank puller on. The mechanic at the LBS gave me what he called a "pickle tool" (probable not the correct name?). It was a wedge-shaped tool that slipped over both sides of the spindle in between the crank and bb. I gave the top a few solid whacks with a hammer, and VOILA! the crank arm came off. Don't know if this method would worry you about ruining your bb tho. Thats why I run the standard Shimano $20 bb, and mines still fine.