Exhaust Downpipe Removal_cbr f2
 

Howdy Guys,

Went to replace the exhaust downpipes on my 94 CBR F2 (I think they have been there on the bike since it was rollled off the production line) and the studs, bolts, and brackets are rusted to hell (see photos below). Basically, theres still one remaining stud left in the engine block (the rest came out as they were rusted together with the nuts) it looks like the bracket and stud are rusted together.

Best solution I can see at the moment is patience and a lot of penetrating spray. I dont want to bend the bolt in the block by trying too hard to move it free.

Just wondering had any had a similar experience and a good way to get around it?


https://cimg5.ibsrv.net/gimg/cbrforu...aa5b09be21.jpg

https://cimg6.ibsrv.net/gimg/cbrforu...c1205030f5.jpg

https://cimg7.ibsrv.net/gimg/cbrforu...c2a11bc5b7.jpg

Couple of ideas:

1: the bracket will bind if it's not coming off straight. Try pushing the other side in and sliding it off evenly.
2: Heat it up. Get a torch and heat the bracket around the stud until its red hot and expands.
3: If the bracket is not going to be used again, cut it off the pipe. The pipe will be out of the way so you can spin it out with the stud.

A couple sharp knocks with a hammer also helps with corroded bolts. Heat + hammer is almost unstoppable

I've also heard that if you get a chunk of wax and heat the bolt up then touch the bolt with the wax, that it'll wick the wax into the threads and help with lubrication. Never tried it myself, but it's a thought

Thanks for the responses guys,

I've tried to level off the bracket using some considerable force and to slide it out but its fairly locked together.

I agree with the heat + hammer but there isnt alot of space to work with right now, I had hoped to get away with not removing the radiator but will see how it goes.

I have a new bracket and pipes ready to fit so I think I'm just going to cut away the two pipes in the second picture which will give me room to work with, then heat up / cut the bracket away if it comes to that.

Ask me about it. Had to contend with 2 snapped studs. Wasted a lot of time and money on torches, stud pullers, impact drivers, hammers, hack saws, locking pliers and what not. Ultimately took it to a car restoration garage. Took him 30 mins to mig weld two big nuts and spray some WD40 and then wrench the studs out.
If you want to give it a go yourself still, I recommend getting the front wheel and forks out. Radiator drops itself nicely and you have acres of space to swing hammers other tools etc

Man, that sounds like an ordeal. Really hoping it doesn't come to that, am hoping a bit of cutting and hammering does the trick.

Need to get my bike back on the road for the sake of my own sanity, using public transport is starting to get to me!

Success.....bit of patience with a grinder and a hammer and managed to get it away. Had to cut the old downpipes away piece by piece but it did the job.

Reckon I'm gonna invest in a new set of nuts and studs instead of using the old ones. They're still as rusted together after a week in oil. https://cimg5.ibsrv.net/gimg/cbrforu...98f8a14d1f.jpg

HELL YES!! Use new stud and bolts!

You've been so lucky getting them out cleanly, but you may have used up all your luck credit by now.

When I did mine years ago I used new stainless studs and bolts and used plenty of copper slip so they'd be easier for the next time.

Think I might have used up all my luck, moved on to fixing the dishwasher after the success of that job and let's just say it's not going so well!!

You can't ride the dishwasher :)