Kibblewhite SS vs Stock Titanium Valves on a TXC 450

[naga]

Well - blew the motor on the 2008 TXC450.
Drive side crank bearing went - shrapnel from the bearing retainer got into the cam chain - cams skipped - intake cam caps snapped (dammit) - which is good - because then the valves didn't hit the piston.
The exhaust cam caps were made of stronger stuff however. Bent the valves. Piston looks OK - I was off-throttle when it went and was fast on the kill switch. No scoring on the skirt or in the jug - just 2 little polished places on top where the exhaust valves contacted.

In my long standing tradition of throwing good money after bad, I'm considering rebuilding the motor myself. That way I know who to blame when it grenades again.

Obviously - I'm splitting cases and replacing all the bearings - and I'd like to add a counter balancer while I'm in there - kinda tired of the paint shaker. I also plan to run 2 base gaskets and the 1.2 head gasket - a little lower compression would help with this crappy gas. I have replacement cam caps (maybe).

If I can keep the parts to well below a grand I'll do it - otherwise I'll tear it down and convert it all to modern art - or boat anchors.

Looking at the stock "unobtanium" valves - and holy moly - that's a budget breaker right there! Kibblewhite (KPMI) has stainless "Black Diamond" valves listed for a quarter of the price of the stock ones.

So, my questions for the people who are smarter than me (all y'all to be honest)... 1) worth it to rebuild? 2) CB worth the extra $300 the parts will run? 3) Kibblewhite stainless valves OK - or do I really need the titanium?

 

[BadMotoWeazal]

Stainless valves will last longer & the weight isn't that big of a deal. I've always had great luck with the KW Blacks & they have always treated me right.

 

[OlderHuskyRider]

This tip is long ways off, but when you raise the deck with extra thick gaskets, make allowances for the cam timing to change, this, I know.

 

[naga]

Thanks gents!

Good to hear news on the Kibblewhites, since I've found them for @$25 each from Summit - versus the $180 or so EACH for the stockers. Yikes.

OlderHuskyRider - that makes perfect since - and BTW thanks for your thread - educational and entertaining.

For the moment the bike is getting a transplant of a 2005 25+K mile TE510 motor...
We'll see how THAT goes.

(thanks Sharpie!)

 

[robertaccio]

my mantra if the cases are split get the SM CB assembly parts installed, its the best mod I ever made to my 08 TXC450 and its still alive and well owned by a friend now.
when and if you do it after getting it properly aligned and pressed in place weld the drive gear onto your crank, oem is a simple non keyed press fit.....if it ever slips you are ffff'd.

 

[sharpie1]

My old '05 510 motor came stock with the CB and still runs like a champ, at probably over 26,000 miles the cases have never been split and the head never off, in fact the motor has never been out of the frame until Sunday so NAGA could "borrow" it for the Sheetiron 300. My '09 450 with no CB is a totally different story...

 

[huskylove]

I would just do the cam caps and all new valves, but use the one valves.


There is a ton more weight in a stainless valve and it's going to hammer on the head vs titanium. I can't even imagine how fast the valves are moving at 10k rpm. It's unimaginably fast.


It was engineered that way for a reason, and if stainless was an improvement it'd probably come stock...

My $0.02 !

 

[naga]

My old '05 510 motor came stock with the CB and still runs like a champ, at probably over 26,000 miles the cases have never been split and the head never off, in fact the motor has never been out of the frame until Sunday so NAGA could "borrow" it for the Sheetiron 300. My '09 450 with no CB is a totally different story...

That's not to say I didn't need to replace the valve cover gasket, breather hose inlet, CS O-ring and seal, gear selector seal, kick starter shaft seal and stator (thanks Dan for the overnight!). Oil tight and runs hard, at least on the 50 miles I've put on it - I feel like I'm riding a legend...
(Thanks Sharpie ).

Now, if I could just come up with a better solution for the intake boot miss-match.

Huskeylove - thanks for the advice - but - I gave myself a $1000 limit for rebuilding the 450 motor - including installing a counter balancer - putting $750 in valves alone in a 6 year old - fairly hammered bike kinda kills the budget. And if the budget is killed - the bike becomes a collection of doorstops...or boat anchors.

 

[sharpie1]

You removed my automatic chain oiler? ...and my homemade stator? Now it will probably blow up.

 

[naga]

You removed my automatic chain oiler? ...and my homemade stator? Now it will probably blow up.

I kept both the stator - and all the old seals - I can put them back in when I give you the motor back...

 

[huskyfrk]

later husky’s came w stainless valves so it can’t be that much of a performance deficit.... instead of screwing w the extra base gaskets and thicker head gasket, why not go the scott summers mod with flycutting the piston about .030 to .060 worked for him.