SAE bolts On my FZ??

[red_rock_beetle]

I just got some frame sliders in and they came with the longer bolts and all, but when I went to take the old ones out I noticed they had a marking of a grade 5 bolt instead of the metric marking for hardness. When I took them out sure enough they have a 5/8" head and the threads are diffrent than the metric bolts that came with my sliders.

Any ideas here guys?

 

[fb40dash5]

If you're talking about the ones I'm thinking of (the ones from the frame into the engine, where about all sliders mount), those should have been allen cap screws, not regular cap screws, AFAIK.

I'm quite confident that they're NOT supposed to be 3/8xSomething thread. Did you buy the bike new or used?

Sounds to me like someone decided to just find the closest SAE thread and roll with it... some combos are really,really close to working. Hopefully that's one of them, because between aluminum engine and grade 5 bolt, the aluminum engine isn't gonna be the winner.

 

[red_rock_beetle]

it was used, it sounds to me like i have two options, one i get allen headed SAE bolts long enoug to work with my frame sliders, or drill, tap, and helicoil the block

 

[fb40dash5]

drill, tap, and helicoil the block

Unfortunately, that's probably the *right* answer. Pain in the rear, but hey, it'll probably be stronger than the plain aluminum threads it comes with!

I'd be concerned about pulling the threads using another SAE bolt... if I were going that route, I'd just as soon use some threadlock on the correct metric bolt.

 

[iSteve]

The last owner may have stripped the original threads and drilled and taped using the SAE thread. If this is the case you would be better off with the same size SAE bolt.

A lot of people strip those threads adding sliders and not using longer bolts.

 

[FinalImpact]

it was used, it sounds to me like i have two options, one i get allen headed SAE bolts long enoug to work with my frame sliders, or drill, tap, and helicoil the block

Were they fine thread or some course thread that got rammed in there? Some may not agree - but if its NFT and you can torque it to specification, you might just leave it alone.

But if you can't torque to spec w/out pulling threads - FIX IT as you mention above. Plenty of hardware stores will carry NFT grade 8 allen cap.
Oh - another tell tale sign; if the bolt came out with its threads all full of aluminum that also dictates you fix it the right way.

 

[fb40dash5]

Were they fine thread or some course thread that got rammed in there? Some may not agree - but if its NFT and you can torque it to specification, you might just leave it alone.

But if you can't torque to spec w/out pulling threads - FIX IT as you mention above. Plenty of hardware stores will carry NFT grade 8 allen cap.
Oh - another tell tale sign; if the bolt came out with its threads all full of aluminum that also dictates you fix it the right way.

Yeah, you can always try the right bolt first, if it pulls threads when you torque it, well there you go, it made the decision for you!

My only concern with that method is if it doesn't pull threads, you can't really be sure if it's still got enough holding power. That's why I said a proper Helicoil is the painful but probably right answer. I don't honestly know what might happen if you hoopty-rigged it and one of them failed in some way, but I personally don't wanna find out.

I'd say odds are anyone that's going to throw an SAE helicoil and regular capscrew in there, isn't someone I want to trust to Helicoil an important bolt in an aluminum engine... but if that's the case, I guess what's done is done.