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-   -   New VP Vice pedals wreck threads on new Rene Herse crank (https://www.bikeforums.net/showthread.php?t=1201810)

FastJake 05-18-20 09:51 AM

New VP Vice pedals wreck threads on new Rene Herse crank
 
Has anyone else ever had this happen? Brand new pedals, brand new crank. The pedals were pretty difficult to install and by the end there were chips of aluminum getting pushed out the other side. :eek:

Yes, I thoroughly greased the threads. No, they're not cross-threaded. Both pedals did the same thing. I don't remember this happening years ago when I installed Shimano pedals on a new Rene Herse crank. I even tried softening the rough edges of the pedal threads with a Dremel cut-off wheel, but that didn't seem to help.

I think I'm going to order some crank taps and try making a pedal thread "die" out of an old steel crank arm to prevent something like this from happening again. I just hope I didn't ruin the crank... I needed the bike and didn't have another good option at the time. Now I'm afraid to remove the pedals.

3alarmer 05-18-20 10:23 AM

.
...I'm not familiar with those pedals, and I've never had the disposable cash to buy a Rene Herse crank set. But given your description, I too, would leave the pedals alone in place if the pedal axles are at straight right angles to the crank arms. But to put your mind at more ease, if there is some mysterious damage that has occurred because of this incident, your cranks are not ruined. There's a simple solution using special boring and rethreading tool, that you use to install a threaded insert (on each side, R + L), and that fixes them right back up. The tool and six sets of inserts is far cheaper than the original price of your crank. Some local shops have them, but not all of them.

If you have an issue later on, and you can't either buy the tool and threadserts or can't find one locally, let me know. But the whole back and forth shipping will cost way more than just finding someone local to do it.

cpach 05-18-20 10:59 AM


Originally Posted by FastJake (Post 21482112)
Has anyone else ever had this happen? Brand new pedals, brand new crank. The pedals were pretty difficult to install and by the end there were chips of aluminum getting pushed out the other side. :eek:

Yes, I thoroughly greased the threads. No, they're not cross-threaded. Both pedals did the same thing. I don't remember this happening years ago when I installed Shimano pedals on a new Rene Herse crank. I even tried softening the rough edges of the pedal threads with a Dremel cut-off wheel, but that didn't seem to help.

I think I'm going to order some crank taps and try making a pedal thread "die" out of an old steel crank arm to prevent something like this from happening again. I just hope I didn't ruin the crank... I needed the bike and didn't have another good option at the time. Now I'm afraid to remove the pedals.

Guessing between the two--I'd bet the problem was predominantly the pedal threads. My guess is it's fine. If you ever messed up the threads on a super expensive crank like that, the upside is that a Herse crank is solid aluminum so you could use a helicoil kit on it if you somehow really damaged the threads.

dsbrantjr 05-18-20 11:00 AM

Might the pedals have had the old 14 mm x 1.25 mm French threads? Did you swap the pedals left for right?

ThermionicScott 05-18-20 12:27 PM


Originally Posted by dsbrantjr (Post 21482278)
Might the pedals have had the old 14 mm x 1.25 mm French threads? Did you swap the pedals left for right?

Spiky MTB pedals with French threads? ;)

http://www.vpcomponents.com/wp-conte...13/02/vice.jpg

I suspect that this is some combination of a small crank ID or large pedal OD in order to prevent a loose fit. I have a virgin set of RH cranks downstairs -- I could try measuring the bore.

bikemig 05-18-20 12:30 PM


Originally Posted by ThermionicScott (Post 21482469)



I suspect that this is some combination of a small crank ID or large pedal OD in order to prevent a loose fit. I have a virgin set of RH cranks downstairs -- I could try measuring the bore.

That would be my guess. I'll bet there's no damage and pedals will now thread in easily to the crank.

ThermionicScott 05-18-20 12:41 PM


Originally Posted by bikemig (Post 21482473)
That would be my guess. I'll bet there's no damage and pedals will now thread in easily to the crank.

Okay, I forgot that my digital calipers have a dead battery. So I tried threading on one of my known-good Shimano A600 pedals -- from the back side of the crank, just in case. It presented no unusual resistance, but I saw some very fine aluminum shavings, too. I think RH is erring on the side of giving us the maximum amount of beef to start with since the crank threads are bound to wear, but those VP pedals might still have sharp or excessively-tall threads for the same reason.

dsbrantjr 05-18-20 12:42 PM


Originally Posted by ThermionicScott (Post 21482469)
Spiky MTB pedals with French threads? ;)

http://www.vpcomponents.com/wp-conte...13/02/vice.jpg

I suspect that this is some combination of a small crank ID or large pedal OD in order to prevent a loose fit. I have a virgin set of RH cranks downstairs -- I could try measuring the bore.

I misspoke, I meant to say French-threaded cranks.

FastJake 05-18-20 12:46 PM


Originally Posted by dsbrantjr (Post 21482488)
I misspoke, I meant to say French-threaded cranks.

Good question. No, these are the new-production version. Definitely standard 9/16".


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