Do I need a top end rebuild?

Hi all
I have a 2008 WRR with 10k kms on it. The first 7 of which where commuting and the last 3 mainly off road.
The bike starts and runs very well and has never let me down. As it's got to 10k I thought I would do a compression test and the results are a little worrying.
The service manual states compression should be around 115 psi. Well I have 75psi dry and 115psi west indicating that the rings are well worn out.
Just thought I would get some comments as to if I need the have the rings done, if the compression test is sus as the bike runs really well and general consensus.
The bike fully modified with air box, FMF full exhaust, programmer.

Cheers Jon

b2jgc wrote:

Hi all
I have a 2008 WRR with 10k kms on it. The first 7 of which where commuting and the last 3 mainly off road.
The bike starts and runs very well and has never let me down. As it's got to 10k I thought I would do a compression test and the results are a little worrying.
The service manual states compression should be around 115 psi. Well I have 75psi dry and 115psi west indicating that the rings are well worn out.
Just thought I would get some comments as to if I need the have the rings done, if the compression test is sus as the bike runs really well and general consensus.
The bike fully modified with air box, FMF full exhaust, programmer.

Cheers Jon

Not sure what to say...

I would probably keep an eye on my oil usage. If I am not using much oil between changes I would leave it alone.

Once I start burning oil I would probably order the Thumper racing Big Bore kit and smile at my future fun.

Hi,

I'm not sure you can get an accurate compression test because of the automatic decompression feature on the exhaust cam. It disengages via centrifugal force and I am not sure the starter spins the motor fast enough to retract it. Maybe someone else with more knowledge will chime in.

Thank
I thought about the autodecomp but was following what the service manual says how to do the compresion test and the standard readings. The difference between the wet and dry readings makes me think that the rings are well worn out. I'm going to try a leak down test n se what that gives?

Only 10 000 km?  The rings shouldn't be worn out at that point.  Do you feel a lost of power?  These WRs can go much further than that without needing a rebuild.  Just look at some of the average mileage people pull on these bikes.  10k is low :)

The decompression test isn't accurate unless you remove or disable the auto-decomp feature.  75psi dry and 115ish wet is what I got when i was going through the same thought process of "man this thing must be getting worn out" this spring.  My bike had 43,000 miles on it and has never burned a drop of oil, but I felt like it was down on power.  Turns out an oil change, clean new air filter, and fixing a burnt up stator was all it needed and now it runs better than ever.  I'm now fast approaching 45,000 miles and it's still running great.

Hey guys thanks for the feedback. I did a leakdown test and although it did not provide repeated results it is losing pressure and looks like the exhaust values may be leaking so I am going the check them. It will be interesting to see if they are out of spec as the bike has been ridden pretty hard.
I'll let you know the results
Jon

"If you don't check for a problem you won't find a problem."

Congrats skierd, do you know of anyone else with high miles?

I checked my valves today, inlet 00.6 and exhaust 0.11 pretty way off spec.
Getting them sorted out this week, hope there is no damage. Funny as the bike always starts and runs really well. Hopefully I will get a power increase after adjustment.

beee wrote:

"If you don't check for a problem you won't find a problem."

Congrats skierd, do you know of anyone else with high miles?

Several others, most post over on ADVRider. There are a bunch of 40k+ mile WR's out there.

b2jgc wrote:

I checked my valves today, inlet 00.6 and exhaust 0.11 pretty way off spec.
Getting them sorted out this week, hope there is no damage. Funny as the bike always starts and runs really well. Hopefully I will get a power increase after adjustment.

So I thought I would come clean... If you look at my valve clearances above and reference them in inches, they are perfectly in spec.  
Due to my dodgy old eye sight I thought I was looking at mm and therefore too tight.  
I had a Pro check my valves and do a leak down test, valves in spec and leak down 5%. All perfect as you guys thought it should be after 10k.
Sprayed the combustion chamber with some stuff to clear out the coke and all is good.
Roll on another 10K of fun in the dirt... Was looking for an excuse to put a big bore on. Oh well happy days.

Jon

add to that.....checking valve clearances is a 'feel' thing....resistance should feel like sliding a card in and out of a deck of cards.

When people post that they're bike is .01 off, and thus putting it out of range/ spec..... I'm always cynical.

If people are getting 40k miles out of a bike, and the service manual states 26,000 mile service intervals......unless you dumped the oil out of the bike, and ran it for miles without oil.....

just go ride the thing....... :)