Im lookin to improve my valves and see all the diff choices of valve kits but id like to know specifics on each one. Whats the diff between them all? Which kit would better suit my needs?
My motor is completely stock but with my RWR CDI box cuttin the rev limiter i'd like to get a nice set of vavles to surpass them floating and possibly causing any probs. Here are the choices that i know of:
- ODP Lightweight Racing Valve Springs
- Ron Wood Racing Dual Valve Springs
- Shim Under Bucket Racing Valve Springs
- Alba Titanium Valve Spring Kit
- And the kits stated from Mr HP.
Now the kits from HP Research, they have stated in their cam choices things like, "the shim under kit $350" for the Web 109 cams, but no valve changes for the HR1 Cams, yet for the HR2 fast trail cams they have "Heavy duty valve spring kit required $110", and for the HR3 TT/Race Cams they have "Heavy duty valve spring kit and shim under bucket conversion kit required $415"

 

I don't know of any advantage to Titanium valves unless you spend most of your time over 9000rpm. The latest cam grinds for race motors are making power all the way up to 10,500rpm. If you rev like that, your stainless valves will pull out because they will probably weigh a 100 lbs more than a titanium valve at 10,000rpm.

If your setup drops off power at 7500 like most mildly built 650's, Titanium is too expensive for the advantages they have at this rpm.

Good Luck![img]i/expressions/face-icon-small-smile.gif[/img]

 

I think you need to clarify you question. Are you looking for new valves or new valve springs or both? If you are getting new valves are you going to go bigger and have the head ported?

Heavy duty/dual valve springs vs. shim unders have been debated a bunch and it comes down to personal choice and whether or not you want to listen to your cam supplier.

That leads to the next question, what cams are you planning on running?

I believe the titanium valves are best left for the hardcore racers that need every edge they can get. For the rest of us it would probably be better to spend the extra $$$ else where.

 

GOOD INFO NUTS! KEEP IT COMMING![img]i/expressions/face-icon-small-wink.gif[/img]

 

I havent decided if i want new cams / piston or not, i kinda am afraid to change them cause i dont want to alter the reliability of the engine. The reason this question came up is that i was recently out runnin around, took the straight away stretch down the road and opened 'er up, my needle on the tach didnt go past bout 7500 rpms but i could move the throttle and the needle wouldnt change, almost like my cdi box and throttle and rpms werent lined up correctly. but it kinda puttered and i let off, now every time i give it to much gas she feels powerless past 6000 rpms, kept ridin to see if it was a fuel injection thing where my self learnin system would correct the problem, but my engine got louder inside and then i started to hear something dinging, my power dropped as well, after hearing the noise gettin louder, i stopped and turned 'er off, went to start it back up and it dinged and pinged real bad, im hopeing its just the valves and not something more serious, but i dunno, so i figured while they have my engine open to look and fix the prob, i could thro a set of titanium valves in there. But i dont know the diff between any of the kits, or what to look for as far as shims/valves/springs, etc

 

Hi is somebody home? You now it all racers would help this guy back before you had all the pissing maches you have now. Please answer this good question.[img]i/expressions/face-icon-small-happy.gif[/img]

 

You need to find your pinging problem first, detonation is like small hand grenades going off in your cylinder! Have you called KMS about any problems with there module working with the wood CDI? what octane of gas did KMS tell you to run?
Lots of Venders selling DS parts so if you want to run on 92 pump gas check out the 11:1 compression piston. cams are for your riding style (low end. Midrange , or Top End) that will tell what valve springs to go with more radical the cam the better spring you will need, as for valves I would stay with stainless you can go 1mm larger with cutting the stock valve seats to fit.

 

I am def goin to get my engine torn down to check for the problem, just wanted to get a lil heads up before hand. I always run super gasoline, 92-93 octane, which is what KMS suggested in their instructions, course it is what Bombardier suggests as well, so i've always run that. I have not asked KMS about the fuel injection wit the CDI, i wouldnt think the combination would cause a problem ?? I am more of a low end/midrange rider personally, i go for the acceleration over top speed, which is why i run a 1 tooth smaller front sprocket.

basically the impression im gettin is, dont get titanium valves unless ur doin major motor work, but all the information is very helpful and educational, keep em comin lol, thanx guys

 

You got to pull your head to see whats going on. If you did float the valves you could have some damage on your hand either the piston, valve or head or all three. Depending on whats damaged will dictate what you need to replace.

Assuming there is no damage, a valve job would be wise since you already have the head off, of course this depends on how many hours you have on it.

Discussing cams you wrote This describes gearing not cams. Cams dictate the power curve throughout the RPMs. For example some cams will give more HP/Tq at 3k rpms, while other cams build peak HP/Tq at 8k rpms. Some cams are more linear in there power delivery while others have more specific peaks. I am not going to even try to suggest which cam is right for you. Maybe you can describe your ridding style and at what rpms you want your power at and then some of the cam gurus can chime in.

Once you decide on a cam, then you should pick the appropriate cam springs for the cams.

My suggestion is to look at it as a whole package not individual parts. Your piston selection will effect your cams, which will effect your cam springs, etc.