I made the mistake of telling a friend that his first motorcycle (a 1987 KZ305 LTD) was in great shape and that he should purchase it (and it did seem fine). I have since learned to keep my mouth shut as now I have to fix something that crept up during his first week of riding.

The head gasket of this fine motorcycle has started to leak on the left side; at least, that's what it looks like. The right side is clean. There is a nice smattering of oil coming out of the bottom of the upper part of the engine and there is a bit of white smoke (not very much) when the bike is revved high.

How should I go about repairing this? Should I pull the head and replace the gasket or is there some magic stuff I can pour in the oil that will seal it up for me? I'm looking to do the least amount of work since this isn't my bike and the owner's draconian sensibilities place the blame on me. Also, I can't find the manual for this bike. Help!

 

Tell him you're sorry for turning him on to a piece of crap and offer to buy the bike ridiculously cheap. Then, do the job properly and keep the bike.

How long does he plan to keep it, and how long do you want to have his friendship?

 

I'd like to keep his friendship for a while to come. I am not sure of the intricacies of changing a head gasket, but I would like to give it a go. My only worry is that I might mess the engine up more than it already is while fixing it. Beside taking the bolts out and pulling the top what else is there to do in there? Valve adjustment? Would I have to check compression? Cam chain and timing? I only have a regular set of tools and don't have a timing gun or compression gauges. I am handy with some Permatex though!

 

If you're going it alone; i.e. without friends who have previous experience, THINK about every step you're doing on disassemble. Make a cardboard template for all bolt locations and approach it like a surgeon. Clean work area, clean rags, extra ziplock bags or cups you can label (as you take apart; not the following week!) Buy some Acetone, Nitryl gloves, and some medium 3M Scotch pads. I would STILL find a manual to refer to (just reassuring to see pictures of your engine at 1AM and convince yourself you're doing it right.)
Keep in mind, you MAY encounter more parts to replace than just the gasket, so wrap your head around the idea, especially on a vintage bike.
As for "messing it up even more," my response is to ask "how well does it work the way it is NOW?" Most mechanical jobs are in your head; it's just step by step, nuts and bolts, specs, and patience. (Not always in that order.)

 

hell, I got a manual if you need some specs (let me double check the year but should work). Kind of a bum deal that you are the one paying for it now though.

 

Great news about the manual! It's nice to know there is one out there that doesn't cost $60 to get $3.50 worth of information.

I think I have decided what to do with this bike though. I will tell my friend that I will not fix it because I don't want to be responsible for the quality of the work done. If it was my bike I wouldn't have a problem tearing into it and breaking it beyond repair; sometimes you have to break stuff to learn anything.

He's going to have to suck it up and eat the loss. I'll bet he can recover a few hundred dollars on Craigslist or maybe make money if he parted out the bike on eBay. Either way, it's not my problem. I didn't break the bike and I didn't hold a gun to his head when he bought it.

 

Any time you buy a bike over 5-8 years old, you're going to increase the risk of some maintenance item (gasket, shims) and/or hard parts (cam chain, valves) being at or near their mechanical tolerance before repair or replacement. That's kinda why I like (and PREFER) bikes in a box, so I get to assemble the pieces and know what I bought.
If your friend has a problem with your line of reasoning (which I do not) then he can buy his next bike without your advice. The bike isn't "broken;" it's USED.