Seized bolt

[Ricco1]

I need to replace the exhaust on my Suzuki GN125. I'm having difficulty removing one of the bolts that attaches the exhaust to the engine. There's not much room to work in as the bolt is very close to the front of the bike frame. The bolt is an allen key type. My efforts so far have only resulted in slightly rounding the allen key slot.

Any idea/ tips how I might get this thing off?

Thanks.

[Guest Hodgy]

You're much better off using hex sockets instead of allen keys, you can get them from Halfords, 3/8th drive tend to be better for use on bikes too as their smaller. Also get the engine warm first, that will help them come out easier

[gravelrashedaprilia]

Nightmare, surprised Suzuki are still using those bolts. Had exactly same problem years ago (GSXR1100) and ended up loosening the engine bolts, to twist the engne so as to gain access to them, then heated them up with a blow torch to get them all out except 1 why is there always 1 f**king, s***** bolt that won't move. Had to drill that out.

[mealexme]

There are a few things you can try

If you heat them up by running the engine, the headers will be VERY hot so be careful.

WD-40 (be careful though as it is flammable, so not ideal near a hot exhaust)

Tightening the bolt to break the seal. If this works, you will hear a crack and there will be slight movement

Hammer time - again to break the seal, give it a whack with a hammer if possible

If the head rounds off, you could use a pair of mole grips instead, although they are not ideal

as a last resort you can drill them, but personally I would take it to t a professional for that

Good luck!

[baggy]

I had seized bolts when replacing the downpipes on the CBR600 I had last year. I used as can of Halfords shock and unlock spray, a couple sparys leaving a few minutes between each spray and they came out without snapping them

[pointblank0]

I've never replaced an exhaust system without shearing off at least one stud. I usually end uo filing whats left into a square and using mole grips after a few hard whacks with a hammer.

[baggy]

I've never replaced an exhaust system without shearing off at least one stud. I usually end uo filing whats left into a square and using mole grips after a few hard whacks with a hammer.

 

I had read some nightmare stories about studs, especially on CBRs but used the stuff from Halfords and took my time.

[Chrissb6]

Try heating the metal around the bolt not the bolt itself metal expands when it gets hot. If you heat the bolt the bolts expands gets tighter go's soft and then snaps off. Result a drill out and re thread. An old hand shown me this trick years ago it works.

Heat the metal around the seized bolt try to avoid heating the bolt, no need to get metal red hot, and then spray some penetrating oil on the bolt. The capillary action will draw the penetrating fluid into the thread freeing the bolt. Hope this helps

[mealexme]

Try heating the metal around the bolt not the bolt itself metal expands when it gets hot. If you heat the bolt the bolts expands gets tighter go's soft and then snaps off. Result a drill out and re thread. An old hand shown me this trick years ago it works.

Heat the metal around the seized bolt try to avoid heating the bolt, no need to get metal red hot, and then spray some penetrating oil on the bolt. The capillary action will draw the penetrating fluid into the thread freeing the bolt. Hope this helps

Would you have to use specific oil, or would wd-40 work? It says flammable, but I have no idea at what point it would combust

[Tango]

Personally I'd use a specific penetrating oil Alex.......PlusGas or the like.....

[Chrissb6]

Most sprays are flammable it’s the propellant that causes the problem as the fluid is atomised when it’s forced out of the can. As said, no need to get the metal red hot, just use a good penetrating fluid. You always have to be very careful when working with heat.