Rant... exhaust bolts

[bexabarr]

Caution!! When removing a stock exhaust... be very careful when removing the bolts!! I just broke 6 of the 8 bolts (I tried the following- tightening a little bit then loosing the bolt. I tried applying heat then spraying penetrating lubricant. I even tried an impact screwdriver). The bolts where completely rusted, and it got to the point that I just wanted the exhaust off so I could start removing the broken bolts. The good things was that the bolts broke off with a few cm sticking out, so I welded a washer and then a bolt and again it broke off this time taking with it the rest of that was sticking out. I'm not even going to try the other 5 bolts since I'm 99.5% sure that they are in the same condition.

The good thing is that my head gasket is blown so I was going to remove the head anyways (after I try a compression test of course). I'm going to try to take it to a machine shop and have it done correctly. Now I just have to figure out if there is a good one in my area that won't cost me an arm and a leg. If it costs me more than the head is worth I guess I'll just buy a new one... maybe one from an 850 :shock: He He. Good thing riding season is almost done...

[bexabarr]

How much will this whole process cost? Because I found some used heads that are pretty cheap, should I should buy them and that way I'll have some extra parts (valves etc)?

[TheCafeKid]

never hurts...but just a warning from the clymer manual itself...used valves from a different head, or mixing up valves from a torn down head are a no no..they suggest numbering or sorting the valves and guides and what not so they go back in the original spot...as each wear a certain way, and failure to do so can cause expediant and terminal failure....so if you buy some spare heads, keep the goodies together and you should be ok

[bexabarr]

Ahh ok. Good thing that your reminded me of that, I remember reading that somewhere. They all worn out specifically to the port they are in (or something like that). So what happens if you blow a valve? Can you get new ones to replace them? What does it mean to do a valve job? Once you identify the warned out ones, then what? I'm a complete novice on most of this and since I'm about to take the head apart I might as well try to check all of this- or not...

[TheCafeKid]

Ahh ok. Good thing that your reminded me of that, I remember reading that somewhere. They all worn out specifically to the port they are in (or something like that). So what happens if you blow a valve? Can you get new ones to replace them? What does it mean to do a valve job? Once you identify the warned out ones, then what? I'm a complete novice on most of this and since I'm about to take the head apart I might as well try to check all of this- or not...

Well it just so happens im learning on these as i go too..but usually when you replace a valve its new...theres no pattern worn in it...so it gets a fresh start in the guide or mayhaps you replace the guide too...they have to be lapped and seated...your manual is pretty thorough and there are far more experienced guys here to help than i. But as long as you have the tools (which i dont, so id either have to buy them, borrow them, or take it somewhere for a valve job) your manual should be able to get you thru it, and if not, ask in the tech forum here...there are plenty of gearheads in here....me..im experienced enough where if something breaks and i can take it apart, i can USUALLY fix it...and most of my motorcycle engine experience is on old vertical twins twins...and most of those are a little simpler...

As far as a valve job, are you talking about adjustment or replacement??
Adjustment is cake, since i have been shown (thanks again to Steve) If ya dont have a manual, get one...it will help a ton with everything. Do a search on valve job to up top...i remember reading an EXCELLENT thread on it with pics!

[bexabarr]

Hey thank for the response. I meant replacement. I know how to adjust them... I just took a look at my manual and there is no way that I'm going to get into that right now. For starters I don't have the tools. So if I have ok compression then I should probably not worry about it right?

[TheCafeKid]

Hey thank for the response. I meant replacement. I know how to adjust them... I just took a look at my manual and there is no way that I'm going to get into that right now. For starters I don't have the tools. So if I have ok compression then I should probably not worry about it right?

EXACTLY..lol If it aint broke...dont fix it...lol as far as the header bolts go...get some PB Blaster and HOSE THEM DOWN good...let that soak for a bit..you have an impact driver??

[TheCafeKid]

ohh...nevermind..youve already broken them...yup..id say take it to a shop and have them drill them out and re-tap them for you..shouldnt be horribly expensive...or you could try a complete new head...just once you get it together check that compression....AND if you need anything for your 750..lemme know...i got some good stuff left and for cheap...check out my add...

[chef1366]

Check THIS out...........

[TheCafeKid]

Check THIS out...........

Thats the guy...hehehe i was just telling him about reading this entire thing....GOOD STUFF... someday ima give it a shot...i do have that TCSS motor out in the shed with a crap top end....hrmmmm...woah buddy...lets just get the cafe running first...LMAO

[nabrams]

If you do get a quote for the work from a machine shop, let us know what they're asking for the job - I'm curious (as others may be).
If they're asking too much:
With 5 of them needing to be drilled out, I'd say get a new head. I've had to drill/tap/helicoil two, so I did it myself - and it took forever. If you work CAREFULLY and slowly (and practice on something else first!) it can be done - see other posts.
Now, once you get it all back together, check compression. Then, it will take 50 miles of riding till everything seats in properly - then your compression should be checked again - see other posts.
Also, when you do eventually put the exhaust back on make sure you have new exhaust gaskets and that there are no leaks - see other posts.
By the way: With a blown head gasket now, measuring compression is pretty much meaningless as compression will be escaping through the blown gasket.

[bwringer]

Some of the stuff they can do with EDM now is amazing:

http://www.brokentap.com

I have no idea what it costs, though.

[bexabarr]

Hey guys, thanks for the links! I actually saw that valve job thread earlier and I've been looking for it for a while. Thanks for posting it! I actually just bought this off fleebay

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=300167683960&ru=http%3A%2F%2Fmotors.search.ebay.com%3A80%2F%3Ffrom%3DR40%26satitle%3D300167683960%2509%26fvi%3D1

Hopefully this will fit and work fine (I'll use my front cam shaft). What do you guys think. I guess it's a win or loose situation. Hope that all is ok with it. But if it's not then I'll just get my head to a machine shop. Thanks again for the responses!

[Nessism]

I'm not an expert on 750's but I think that head will work (good price too).

I strongly suggest taking the head all apart and at least replace the valve stem seals. I also suggest you use a micrometer on the valve stems themselves to see if they are worn (service manual will give specs). Take apart both heads and mic. all the valves - use the best ones. A light lapping wouldn't be a bad idea either - key word, light.

Good luck.

[gsgeezer]

For others who haven't broken theirs yet: KROIL