chemomche

Hi, last Saturday i took my Vtr to the track for the first time.
The first session it felt so big and heavy, a have been on this track before but with my KTM sumo bike and it was completely different.....lines, speeds. The second session i started to get used to the track and finding the correct lines for me.
Then came the third session when i was almost ready to stat pushing the bike when suddenly i heart strong ticking noise from the engine, metal hiting noise + loss of power. I polled over and killed the engine. It sounded as if its working on one cylinder.

Due to alll the things i have read for the ccts i think it is cct fail, am i right?
How to precced from now?Should i open the heads, and which one to start with?
I have read that cct fail when riding at low rpm and open the throttle at about 3k, but with me it happened at 6-7k

And i am just pissed off....friday i bought new battery and woke up at 6 am to change the R/R wiring + adding aluminium radiator to it to make the bike ready for the trackday

8541Hawk

Well it doesn't sound good but the first thing i would do is pull the valve covers and check the valve clearances.

If one set of valve is way out of spec (to the open side) Then that is the head that grenaded...

chemomche

opened the front cylinder head cover and the in valves had 4-5mm clearance
removed the head and here it is...two bent intake valves





the weird thing is thaty the cct seems to be ok


So i will be looking to buy vavles and valva seals.
The exhaust valves seem ok, i poured petrol in the head and they did not leak. However i will have them check.

klx678

Keep it from happening again, trash the OEM tensioners and put in manual ones. This is the only bike that I've come across that suffers virtually instant catastrophic failure when the tensioner fails.

FL02SupaHawk996

+1

7moore7

You sure it failed? Could just be carbon buildup...

chemomche

How can carbon buildup cause 2 bent valves?