Bolts in place of spirol pins?

[cooperino]

Originally Posted by finsruskw

weakest link, yes.
It's doing what it is supposed to do then.

LOL.. good point!. You really sort of want it to break when intended.

[cheesedawg82]

Originally Posted by finsruskw

weakest link, yes.
It's doing what it is supposed to do then.

For sure. I know I'd rather bust a pin that costs a quarter than expensive parts. That's one of the reasons I've been playing with old cub cadets instead of racing. Some people truly enjoy finding the next weakest link, though. Who am I to judge someone for that?

Judge not, lest ye be judged. Matthew 7:1

[CADplans]

Put a Grade 9 bolt in, the bolt will be there long after the spirol is shards on the lawn,,,

https://www.amazon.com/dp/B07CVMJ13M/ref=biss_dp_sa1

Use a bolt that has 1 1/4 length unthreaded,, cut off the excess sticking out of the nut.

[RAC65]

When we pulled it would've been in what would probably be called a stock "limited" class. Used a 100 narrow chassis and for most of it's track life had a OH180 Tecumseh in it w/ about a 13.5:1 compression ratio and high ratio rockers (because of course you had to run the stock cam). Probably north of 30 hp & over 7,000 rpm. 24-26 gearset in the tranny. Would run down the track in high gear 900, 1,000 & 1,100 pound classes & in the 24 tooth at 1,200 pounds.
Ran a bolt in the back coupler and of course roll pins in the front end for the clutch. Never ever even a hint of breaking either. The top drive pinion isn't at much risk of being broken!
The same tranny also did a stint with a 53 cube single in front of it & 16 inch rubber on the back. Drive pinion seemed to handle that too VW clutch on that motor though.
Did break a stock driveshaft once. Some of the stock shafts had an extra roll pin hole there somewhere toward the middle (don't know what for). Broke it in half right there, that makes a racket at around 6,000 rpm.

[dodge trucker]

I did a bolt in place of a spirol pin once. On a 1200 I put a bolt in the deck lift handle where it connects at the bottom.

[sawdustdad]

Originally Posted by CADplans

Put a Grade 9 bolt in, the bolt will be there long after the spirol is shards on the lawn,,,

https://www.amazon.com/dp/B07CVMJ13M/ref=biss_dp_sa1

Use a bolt that has 1 1/4 length unthreaded,, cut off the excess sticking out of the nut.

Why stop at 9??? Turn it up to 11!!

https://youtu.be/4xgx4k83zzc

[ColoradoCadet]

I was wondering why not use bolts too. I had to look them up. The spirol pins (coiled spring pins) are not like a shear pin, so I don't know that they will break any quicker or later than a bolt? They are designed to flex, provide uniform strength and not come loose due to vibration. Very interesting little piece of engineering.
https://www.spirol.com/library/sub_c...enefits_us.pdf

[SLS327]

I prefer the spirol pins vs split roll pins. Everyone stocks the coil or split pins, but not spirol. Be sure to use a pin punch on the spirol, if you get the small punch in the middle it will lock it up.
I put a grade 5 bolt in the rear coupler of a creeper drive. It should be a spirol pin though. I ordered qty 10 1/4 x 1-1/2 from Mcmaster.