Valve Guides

[Guest]

I am in the process of cleaning up a GSXR1100 head. It appears to be in pretty decent shape, but it looks like it's going to need valve guides. Is this a DIY job, or does it need professional attention? If it can be done, what would the procedure be?

[Nessism]

The service manual lists the procedure, but it's abbreviated to be sure. A person could do the work in their garage but you will need quite a few tools in order to replace the guides, ream them to proper size, and then perform a valve seat touch up afterwords (replacing the guides changes how the valve sits on the seat, thus the need to do a valve job afterwords).

I've done garage valve jobs on an 8V GS1000 head, and have the tools to do the guides but haven't had the need yet. The tools were not cheap - several hundred dollars. Unless you are a nut job like me I'd take the head to a motorcycle specialty shop and pay them to do the job.

[rapidray]

Send the head to someone like me or another shop owner that specializes in MOTORCYCLE head work to get the guides replaced & a valve job done. Ray.

[Big Jay]

I would not recommend that you try a guide change at home. Even if you managed to get the old ones out and the new ones in straight, you then need to be able to hone them to size, then do the valve job.

Ray gave you the best advice, and STAY AWAY FROM AUTOMOTIVE SHOPS.

http://aperaceparts.com/mailers/heads.html

[sharpy]

Its easy. Hammer punch and fridge. Heat the head in the sun, while its on the concrete and warm bash the guides out. Go to fridge and get frozen guides and bash them in with a block of wood. Still have the head on the ground for support. When all done place valves in head and give them a good wallop to seat them. Assemble the head and make sure u check the shims while it on the bike, start the bike. Go for ride. Easy as. PS Only one hint in there is true. Take ure pick. Or take it to a cleverier person. Sorry skipped skool.

[trippivot]

Are you measuring or wiggling the valve to feel if it is excessive clearance -never mind- I'll assume you know what you are doing.

heat the head to 450 in the oven and tap them out with a like diameter drift.

have the new guides in the freezer (overnight not 10 minutes)

pop out the old - re heat the head pop in the new ones..

ream to perfect diameter....

[Nessism]

Are you measuring or wiggling the valve to feel if it is excessive clearance -never mind- I'll assume you know what you are doing.

heat the head to 450 in the oven and tap them out with a like diameter drift.

have the new guides in the freezer (overnight not 10 minutes)

pop out the old - re heat the head pop in the new ones..

ream to perfect diameter....

450F seems a little on the "hot" side doesn't it? Personally, I think 350F seems more like it but then that's just my guess (after searching out info on the web). If you get the head too hot there is risk for warpage and for loosening of the valve seats.

While taking the cylinder head to a professional is good advice for most, I enjoy tackling some of the more technical tasks sometimes and choose to perform my own valve job on a recent engine rebuild. I'm not going to say the job was easy per say, but it certainly is doable by tech savy people willing to put in the time to proceed methodically. Changing the valve guides would add one more task to the list, and I haven't done this yet, but I wouldn't be afraid to do so.

My understanding is the Suzuki service replacement valve guides are oversized on the OD compared to the OE guides. The service manual calls for reaming the hole in the cylinder head to 12.2mm before installing the new guides. I believe Suzuki was concern that the guide hole may become oversized during valve guide removal so they mitigate this risk with the instruction to ream the hole and install the OS guides. Before proceeding with guide replacement using aftermarket guides, I think some research is in order to make sure the guides fit with the proper interference fit to the head. Last thing we want is for a guide to fall free.

[trippivot]

NOPE. but do not shoot for a higher temp. it'll take long enough to get it over 400F if you can stand the smoke. I don't care how many times you wash it there is always a huge stinky cloud. use a temperature pencil so you know when it is there

trying to OVERLY force something in-OR out at a low temperature will potentially cause terrible damage and improper alignment. Especially if it gets stuck and never fully seats in place and then hope the seal seals against the mutilated end you caused from wrong tools or excessive force.

HEED MY WARNING this is one of the biggest problems of do - it - yourselfers attempting head work - heck most guys can't operate the measuring tool properly,let alone get the confidence to heat up such an expensive-delicate part. - practice on a ATC 185 or a small 4 cycle engine head before ruining a GS head.

BTW the seats are in at a different interference fit and require molten mind bending magical secret government processes to extract and install -- LOL

[Big Jay]

Couple of suggestions.. 450 is way too hot. Seats will fall out at that temp.

Putting guides in a home freezer will not shrink them. Most freezers only get down to +20 degrees. Just enough to keep food frozen. You can mic a guide, then put it in the freezer for 12 hours them measure it again. You will see. If you want to shrink a guide you need dry ice or liquid nitrogen. Both are about 100 degrees below zero and will shrink a guide about .001" ( note; we do not freeze guides to install them )

YThe factory service manuals are way out to lunch when it comes to guide installation. Guides should not be reamed, only honed./ We get a lot of heads in for repair where the shop tried to ream them.

Start with a guide with the correct I.D. and hone them with a guide hone to size after installation.

THe other poster is correct about Suzuki guides being oversize and the manual telling you to ream out the head. Don't butcher the head like that. Just get an aftermarket guide that is the correct size. http://gszone.biz/guides.html

Jay

[fasterzx]

Big Jay - How come you are not working on my head that has been down there for a month instead of spending time on this forum - just kidding take your time and do it right but I would like to get it back together before summer

[Roger P.]

I'm only into this head for $100, so I'm not terrified of ruining it. You get what you pay for, as almost all the cam cap threaded holes that the cover retaining bolts go into are stripped, and the valve cover has a nick out of rim that will need to be welded up. It's entirely salvageable, just needs some effort. I think I'll drill and tap to 8mm and run some studs out to snug the cover with aluminum disks and seals, with some acorn nuts. Should look butch!

The valves came out easy with some taps with a hammer and a deep socket to pop the retainers. The valves looked a little dished around their margins, and the seats have a mottled look, like oil was trapped and burnt there. The GSXR that this came off of must have been an oil burner, as the exhaust ports were caked with hard, crusty burnt oil. Cams and followers were in good shape though, as were the cam bearing surfaces. Cams have slotted wheels, I don't know if those are stock or not. They have to go anyway for the GS sprockets.