Engine Builders - Take a Look

[BacNBlak]

All,

I am pulling the motor on my 08 CBR 1KRR to fix a damaged motor mount (long sotry). Either way, the bike has 10K miles, 1,800 on the track. I bought the bike brand new and have always run 93 octane, 'name brand' fuel. Its never had stale fuel in it, driven daily/weekly. I pull off the throttle bodies and this is what I find on ALL 8 INTAKE valves. Pic one is what the average build up is. Pic 2 is the worst valve.

To the guys who have been into these (types) of engines, is this a sign of worn valve seats or bad fuel? Bike has run FLAWLESSLY since day one. Its not an oil burner, and def not a slouch.

Thanks in advance for the help all!

 

[BacNBlak]

My buddy just brought up a good point. My quickshifter only controls the 4 primary injectors so the 4 secondary are still firing when I shift. That fuel, emissions, ect could cause this possibly. Valve seats would look WAY worse I think.

 

[avizpls]

Is it hard? Just looks like some carbon build up. No huge shock to have that in a 10k mile engine.

 

[betarace]

Doesn't look awful to me, would run a tank of BG44k and call it good

 

[BacNBlak]

Thanks, all for the replies. I think its a fuel quality issue.

 

[Matt]

looks just fine to me. in fact, that's really clean for 10,000 street miles.. it's a good thing honda's tend to run hot, it keeps them clean like that.

I recently worked on an R6 that had 2700 street miles, most likely crusing for chicks with a helmet on the side of the rear seat. It's carbon build up was so bad one of the #3 intakes valves wasn't closing all the way.


run it!!

 

[ninjamansc]

Just to satisfy your curiosity, a compression check would tell you for sure.

 

[Matt]

ninjamansc;160071 wrote: Just to satisfy your curiosity, a compression check would tell you for sure.

a leakdown test would give a better answer.

 

[JRSMAIL]

Matt;160126 wrote: a leakdown test would give a better answer.

This ^