[Andy Salmonsen]

Thanks again for all the advice.
I’m gonna order the leak down tester to be on the safe side. Oil wasn’t milky. I’m gonna change the head gasket when I do the rebuild anyway so that should fix the problem regardless.

The only thing that sucks about putting a new can chain on is you have to take the flywheel of which is a pain. Can I put a new cam chain on in a different way?

Ill tell you guys what I noticed once I get the leak down tester.

Thanks

[Aussiecrf230]

Andy,
How long have you had the bike?

Just wondering if someone may have changed the valves to stainless in the past.
Measure your valve clearances you have at the moment that will give us an idea if they are worn.

Jim & Neil,

Is there an easy way to determine if they have been changed in the past?

[Andy Salmonsen]

I have had the bike since the beginning of June 2019. They guy I bought it from owned the bike since 2009 i think. He said the first guy was like 20 and just wanted to get rid of the bike I think. The guy bought I bought it from was a weekend warrior and mostly went to the track. It was all oem when I bought it the only thing I've done is put a full fmf exhaust system on it. He never gave us any paper work of any rebuilds or maintenance or mentioned that he had done anything to the bike. The maintenance part of the manual has nothing written in it. The bike has run great since i bought it and even when it did start smoking it was still running good. the bike doesn't have an hour meter which sucks but my guess is somewhere around 100 hrs. Ive mainly ridden the bike on trails, the desert and the track once. Im not the type of guy to ride balls to the walls with the throttle wide open i like to kind of cruise in the mid rpms.

[Andy Salmonsen]

Also yes i did hold the throttle wide open when doing the compression test and kicked it multiple times and it still came out to 50 psi or just below that.

[Andy Salmonsen]

Ok, I finally got the leakdown tester and was just able to do a leak down test. My results were these.

1. Air was leaking down to the oil dipstick so the rings are worn
2. No sounds coming from intake side of top end so intake valves should be good
3. There was a change in the pitch of the air when my dad put his hand on the exhaust outlet. I think this may mean that the exhaust valves are leaking. I double checked that it was on the compression stroke by moving the rocker arm and it was free.


So from all that what i think i have is some worn rings that need replacing and exhaust valves are leaking a little bit. Cylinder leakage was very low on the tester which was interesting but cylinder leakage did increase as psi fell from the air compressor. To get the right reading for cylinder leakage do you have to check right when u connect the gauges to the cylinder or wait a little bit? Please let me know your thoughts on this so i can make a good decision about possibly sending the head in.
Thanks

[Aussiecrf230]

It is normally the inlet valves that wear.
Sometimes a bit of carbon can cause an exhaust valve to leak.
You can try it and push the exhaust valve down too see if it clears and seals whilst test leak down.

Have you measured your valves clearances?

The clearances you have and the shims that installed for each valve will also help determine best way to go.

Mind you if the head is 12-13 years old that is a pretty good life.

[JimDirt]

I agree with Ray on this .... That maybe it is carbon on the Exhaust valves .... especially if you just use pump gas , it will carbon up a bit , as pump gas by itself just does not burn very well ..... I run a mix of Av Gas (110 octane low lead from the local airport) and non Ethanol Premium , though pump gas is just fine , it will actually have less carbon buildup by adding something to boost the octane .......

As far as the hours on the bike , with 100+ and not knowing how the maintenance was done ... a freshen up will most likely solve all or most of your issues .... As far as removing the chain without the flywheel .... No , you must remove the flywheel , and do it with the correct puller for that engine , also take note of that brass piece at the end of the crankshaft , DO NOT tighten the little nut that comes with the puller all the way down , leave just a slight gap from being snug , so you can turn it a little each way , if you tighten it all the way , and tighten the puller to remove the flywheel , it will crush that brass fitting and you will lose oil to the engine , and the crank will be toast , along with the cam or anything else in the engine that requires oil , so be extra careful when pulling the flywheel , that part is sometimes overlooked at the cost of a new crank ....

On a related note , my 02 450R has over 400 hours on the current piston .... if that says anything about how taking care of a engine lengthens the life ........

[Andy Salmonsen]

Ok, my dad and I went ahead and took the top end apart today and everything looks good. Checked the shims on the valves and both are still in spec and well within tolerance. Cylinder looks really good no blow bye at all, no cracks in cylinder wall.

Can we soak the head and cylinder in engine cleaner or is that a big no no? Still trying to decide on wether or not to send head into ken and get it worked on, although is shims are good and no real leaking do we even need to send the head in?

Please get back to me ASAP, thanks

[JimDirt]

If you are unsure , try taking some fluid (nothing caustic that will eat rubber) like gas or rubbing alcohol , and pour it down the ports *both Intake and Exhaust* (enough to see if it is leaking , like a 1/8 or 1/4 cup or something , and let it sit for a few minutes (2-3 minutes) then tip the head over and see if it is damp in the combustion chamber area at the valve faces , if there is dampness , then the valves are leaking and should be done ....

[Andy Salmonsen]

Ok, I’ll try taking some gas to the valves to check for leaks tomorrow morning. Thanks for the advice

[Andy Salmonsen]

I did the gas check in the valves and there were no leaks so I put the head back on the bike. Right now I’m just trying to figure out the timing. I have the crank at TDC and I keep trying to align the marks on the camshaft but every time I do one mark ends up just above the top of the cylinder head and the other is just below the top of the cylinder head. Is that close enough or do I need to get it spot on?

[JimDirt]

If you have the Tensioner in and set , and the mark on the Clutch side big round plug is aligned , and the small round plug ignition side mark and the 2 slash marks on the cam are LEVEL with the head , then you are lined up , it is best to check this with the plug out so it does not push the engine forward or backward a bit ...... all 3 should be aligned when it is correct , otherwise , you may have it off a tooth , also make sure you are on compression stroke , the cam lobes should be facing rearwards around the 2 o'clock position , all valves should be closed and there should be lash/free play , it looks close to me from the pic , but the other marks should be off slightly as well , if it were in time , so recheck and make sure all 3 are right on the marks , if the chain is not stretched then it should be on , if it still won't align , then I would say the timing chain is stretched ...and needs replaced .....

It looks like it is the compression from the plug causing it to be off slightly , but again , without seeing the other marks , it can also be the timing chain is stretched .... so double check everything ..... to see if it is compression , or a stretched chain ....

[Andy Salmonsen]

Ok, I aligned the crankshaft plug directly on the timing mark and the camshaft marks we’re lined up perfectly so it’s was an error on my part with putting the crank at tdc.

[Andy Salmonsen]

Sorry to keep posting questions but I have one last question. I’m almost done with the rebuild and am getting close to being able to start the bike up for the first time. I was curious on the break in procedure for the rings. Do I need to do an elaborate procedure to break the rings in our can I just go ride it right off the bat?

Thanks

[Aussiecrf230]

Andy,
Best thing for new rings (even new engine) is to make sure to limit idling or high revs. I assume you put some oil on the rings and the bore for initial lubrication.

I find a incline and run up that at wide open throttle in a high gear.
After a say 5 seconds back off. Repeat several times.
If it is flat where you live that will do, I have used the slope to limit speed.
If you don't have the room, even a second or two at wide open throttle helps bed rings.
Basically normal riding really.
The idea is the the full throttle allows the gas pressure to force the rings firmy against the bore. When you back off for several seconds that allows the engine oil to cool things down and wash any metal particles away to be caught in the filter. We are talking really fine bits of the ring material.

I am sure Jim will chime in with how he beds his engines in.

Make sure you have filled and bled the radiator to keep it cool too.
Recheck any cables, wires etc before you start.

Sounds like you and your Dad have had a good time with this rebuild and learnt a few things on the way.