OT: How badly did I 'screw' up?

[ti_boi]

So I recently accidentally stripped a few of the front-most threads from my crankset by trying to screw in a set of pedals at an incorrect angle. I then tried another set and was able to get them to mount into the crank with a little persistance and effort. I plan to replace the set in the near term, but was wondering if it would be OK to ride. The pedals seem to be secure and they seem to be flush with the cranks.

[bobswire]

I don't see why not if you only stripped a thread or two. It has happened to me once or twice through the years along with a bottom bracket but I've always been able to correct it. A pic is worth a thousand words.

[AngryScientist]

i think this is actually "on topic".

depends on how many of the threads you killed. if there are more than half of the threads still engaging, and the pedal is sitting squarely against the crank arm, you're probably safe.

[dave thompson]

Thread the pedal in from the backside of the crank arm. That will clean any gizzed up threads.

[Steve in SLO]

Thread the pedal in from the backside of the crank arm. That will clean any gizzed up threads.
I was thinking the same thing, but without the 'giz' (or is it 'jiz'?).
Alternately a trip to the LBS or to a friend with a pedal tap to clean the threads from the backside may clean them up a bit better and 'retap' some now cocked threads.

[ti_boi]

Thread the pedal in from the backside of the crank arm. That will clean any gizzed up threads.


I did and I think, perhaps, that was the case. I used the allen wrench from the backside and that seemed to work!

Thanks guys for the response. I did kill a few for sure, but maybe the majority of the threads were still around. Gotta get out and about to see! :beer:

[RPS]

Typically most of the load is carried by the first few threads, so if you damage a couple the others would pick up the slack. Assuming it’s a steel pedal axle and aluminum crank arm, the axle should be much stiffer than the aluminum threads so I’d personally feel comfortable riding it (provided it was just a couple of threads). Having said that I’d keep an eye on the pedal to make sure the pedal doesn’t back out unexpectedly.

If you've already gotten it started and tight square on the crank arm I'd leave it alone. That's my personal opinion based on not seeing what can be gained by removing any metal after the fact.

[RPS]

BTW: What's the OT for? Is there a hidden message here? :confused:

[ti_boi]

BTW: What's the OT for? Is there a hidden message here? :confused:


No not at all. Just wasn't sure this was on topic or not. But I guess it was afterall. Believe me. I was happy to get these pedals on there. I gotta get a bike stand to work on the bike. It helps!

Thread drift alert: Cool thing about it -- before I tried to remount another set of pedals -- and stripped it; I had some pedals on there and sold em, took that money and bought my little girl a great new bike for her b-day!

[Dekonick]

A little JB weld and they can re-tap the threads.

[luv2bike]

Hi,

From a Machinist's Handbook - 3 full threads of engagement give you 90% of the designed thread strength.
I am not sure if that differs based on the fine threads on the crank's pedal threads compared to a course thread but it has to be close.

[Bob Ross]

i think this is actually "on topic".

Perhaps he meant "Oh Thit!"

[dave thompson]

I was thinking the same thing, but without the 'giz' (or is it 'jiz'?).
Alternately a trip to the LBS or to a friend with a pedal tap to clean the threads from the backside may clean them up a bit better and 'retap' some now cocked threads.
Hard G, and it's an English term that's only slightly more polite than 'buggered'.

[ti_boi]

Hi,

From a Machinist's Handbook - 3 full threads of engagement give you 90% of the designed thread strength.
I am not sure if that differs based on the fine threads on the crank's pedal threads compared to a course thread but it has to be close.


Cooooool!

[bike22]

bring it to a shop, have them run the pedal tap through the threads to clean it up.

i have a set of cranks where the half of the pedal threads are totally stripped out; totally gone that see 250-300 miles a week with nary an issue. probably close to 10k miles on that set since a dummy (me) stripped them.

[champ]

+1 on Dave's suggestion. If that doesnt work try to tap the threads. That will clean and straighten them

[rpm]

Slight thread hijack. How tight do you have to tighten your pedals? My theory is that reverse threading keeps them from loosening while riding, so I hand tighten pedals with just a little touch of the wrench at the end so that they're easy to get off when I want to.

I've never had a pedal loosen while riding. But I've had bike shop mechanics really wang down on them, and then I've had to take them in to be removed when an ordinary pedal wrench and my strength won't move them.

[ti_boi]

These are tight! I won't remove them. I agree they may not need to be tightened so much i wanted to make sure they were in there straight!

[keithreynolds]

...How tight do you have to tighten your pedals? My theory is that reverse threading keeps them from loosening while riding, so I hand tighten pedals with just a little touch of the wrench at the end so that they're easy to get off when I want to.

I'm not so sure that just riding will tighten. I've seen a couple of drive side pedals fall out, and in my mind the drive side could un-thread. You should take a look at the specs of your pedals, 40nm of torque should be about right.

[RPS]

I'm not so sure that just riding will tighten. I've seen a couple of drive side pedals fall out, and in my mind the drive side could un-thread. You should take a look at the specs of your pedals, 40nm of torque should be about right.
Interesting .... I've only seen one fall off and it was also on the drive side; although I think its coincidence. Why would there be a difference between drive and non-drive? :confused:

[Fixed]

run a tap
cheers
imho