No compression....checking valve clearance

Well, since you are from Katy, I am sure you will be able to find someone to come over and give you a hand... Katy is now officially a bedroom community of Houston I guess... Anyway, with no compression, this can only mean two things...

1. rings not seating at all
2. valves stuck open (probably bent)

Honestly, if the bike is turning over, I doubt the rings have absolutely no seating as I have never seen this... more likely the valves are bent and not closing. Do you have a compressor? If so, put the crankshaft to where the 1/4 cylinders are at TDCC (top dead center compression stroke) and find a rubber fitting that will fit into the plug hole to where air won't escape. I use the fitting from my compression tester. At TDCC both valves are closed. Blow air into the plug hole... Get someone to feel/listen for air coming out the exhaust. If it is, the valves are bent. You could also remove your exhaust system and poke something in there and FEEL for the valves hanging open... like a pipe cleaner or wire. In any case, I would buy a torque wrench and head gasket... You just have to remove the nuts (and two small bolts on the ends of the head) and gently pry the head loose and then pull it off. When you do, since there is no pressure on the valves from the cam lobes all the valves should be shut. I bet they ain't. The likely cause of the bent valves (if they are bent) is the cams were put in wrong.

Anyway, at this point, the valves that are bent need replacing and the length of the valves adjusted (grind valves). New valve stem oil seals need to be installed. and the new valves lapped in. The guides/seats need to be looked at and all carbon removed. It takes about two hours to do this job.

While you are in there, I would also remove the block and check the cylinder bore to piston clearance. If the clearance is within spec, then all that is needed is honing of the bores and replacing the rings. This costs only about $100 total for the hone and rings (if you can find the right rings). If the cylinder bore to piston clearance is outside spec, new pistons and cylinder boring is required and this is very expensive and I personally would look for a good used block/piston set on eBay. You can generally pick one up for under $100...

Anyway, if you need help with anything, just holler. Ron is close by as are other Houston folk who are very capable of helping out.

WG-

Thanks. Bad news as of this morning...after verifying #1 was at TDC, I looked down the spark plug hole with a flash light and could clearly see damage in the cylinder. I'm new to this but I guess I would describe it as one side of the cylinder wall being pushed in and you can see the edge of it....Gee....it sounds worse when you type it out, don't it?

You know...at this point I actually don't fee very bad seeing how I have very little money in the girl. It can't get any worse, right? Too early for a beer.

And yep...I've found some local help. KZRider rocks.

I would be curious as to how that damage occured. In any case, you can generally pick up a matched block/pistons on eBay for under $100. Check them for cylinder bore to piston clearance and then if in spec, hone and re-ring and you should be close to rolling.

WG-

I went ahead and pulled the head off last night. You know, that hunk of metal was there when I started the tear down, but halfway thru it wasn't any more (i'm not insane). After pulling cylinder head...no sign of stray piece of metal....pulled block....no sign there either. I did see indication on top of #1 piston of valve impact. When I drained the oil I didn't see any signs of "material" in the oil.

So now I'm at the point of checking/replacing the valves, ensuring the pistons/head are in spec, and putting it back together again. I would think if I do that correct, she should be running.

This is way cool. Talk about letting the smoke out of the bottle!

Dan, in the filebase is an article on a home made valve spring compressor I think. It is likely in the non-model specific section. If you can't find it holler at me. You can also get a valve spring compressor from z1enterprises.com. You MUST have the proper size adapter so it just slides over the bucket and you can't buy one at the autoparts store. You will likely want to pick up a gasket kit. A kit contains not only the gaskets you will need but a set of valve stem oil seals. Also, pull off the cylinder block and measure the cylinder bores and pistons. The difference between the measurements is the "CLEARANCE". A service manual will recommend NINE measurements... one is taken in three angles towards the bottom of the bore, three at the middle and three towards the top. This will help pinpoint cylinder ovaling (out of round). If the cylinder is round, there is a specific point where you measure the diameter of the bore. You will then measure the piston diameter at a specific point. The difference is that clearance. If the clearance is smaller than the spec, you can hone and rering after honing and this will restore performance to a large degree.

Once you disassemble the head, put the valves in the seats and try turning them in the guides. If they move easily, they won't be bent. If they bind, they are bent. Sometimes, the bent valve is hard to see. Also measure the LENGTH of any good valves. Make sure the stem length is in spec. If it is too long, you can sometimes grind some off the end but stem lengths that are too long often mean the seats are worn. Stem length measurement is the best indicator of seat wear.

Last thing... find out if the parts from a J motor can swap with the 1100... is the head the same? I am not sure but if it does swap, as well as the block/pistons, this may give you some additional used parts options. There are probably lots of folks who know more about the 1100 than I do on this board...

WG

10-4. Thanks for the guidance.

Texdan:

How you coming with your bike? I live down the proverbial road (Alvin) and I have one of those valve spring compressor gizmos.

Mcdroid-

I'm gonna need it. I'll be hitting the valves this weekend. I've read the instructions on the homegrown valve spring compressor and think it would work, but I'd like to get started on the valves as soon as possible. PM me if we can get together to get that valve spring compressor. Thanks!

My buddy roy-b-boy-b makes adapters up from old buckets and then I just welded a nut onto the end of a big c-clamp but a mooched compressor would work just as well.

Michael, I guess having bought a compressor tool with adapter, you have gone through a head before and will be able to give Dan a hand or at least some tips? If so, I will drop out.

Dan, if it turns out you need some tips or any help with the head, go to my web site and find my phone number. I will be on my phone tomorrow as I will be working all day. Good luck!

wiredgeorge wrote:

Michael, I guess having bought a compressor tool with adapter, you have gone through a head before and will be able to give Dan a hand or at least some tips?

Yes George, I have, and I was amazed how well it went with the correct tool. Don't however, bow out too soon, Texdan may opt to make his own:lol: