SS vs Ti valves

[mirror_racing]

I have heard two sides to this story but which is better? Ti valves or +1mm SS valves? I am building my CRF motor and am wondering what to run. I plan on putting a Hotrods stroker crank with a big bore cylinder and CP 13:1 piston. Also plan on the head getting a basic port and polish...

A factory CRF 450 in 05 did come with Ti valves stock correct?

[buck440]

the shop that builds my motor 07 kx250f said ti valves are better performance wise but need replaced more often and ss valves last longer and are cheaper.

wasn't much help but they told me i would be better off with ss valves maintenance wise.

[JAG Motosports]

the ti will rev faster becauce they are lighter ... u can also run a lighter spring which is a bit more power. The ti are coated and when that wears off they zero quick... dirt and heat cause it.. if u do bronze guides and copper bryillium seats both dispense heat alot better and valves will last longer.

[mirror_racing]

Awesome. That's s good tip! I want to push as much power as I can out of this thing to haul my 200lb fatness around the track lol

[JAG Motosports]

I personally think the ti valves are worth the cost if ur after every bit of performance... they do cost more.... my mechanic does a great job and very reasonable so pm if u need help

[mirror_racing]

ok thanks I appreciate it!

[josborn]

Just put the stainless valves in it and forget it. My CRF hauls arse with stainless intakes and stock exhaust (steel). Ti works in the yamaha's but not in the Honda's, unless your into tearing it apart to check them every couple weeks.

[MXin700R]

If they work in the Yamahas and not the Hondas then theres something up, a reason for this.
The Yamahas when it comes to size of valves are running 5 exhaust valves if you wanna look at it that way. All the valves are basicly the same weight and take springs close to checking springs when it comes to pressures lol.
The TI quality and workmanship may be a reason.
When it comes to rev quickness, no one can listen to two engines and say which one has TI and which one has SS if the build and tune are equal. Its not enough to justify for most people IMO.
The main reason the Raptor builders run TI on some builds is because once you get to a +3 intake valve with a race cam it will float the valves with any valve spring available at the moment(and have to use lash caps).
If you want to make TI last as long as possible, run copper berilium seats.

[mirror_racing]

Wait, the stock valves are steel not Ti? I was told that they were Ti.

You think I will have to check the valves every couple of races running Ti?

[josborn]

Yep, only intakes are Ti on the CRF. I know allot of guys go +1 on them, but I think you're opening a can of worms, because to take advantage of that you need porting, carb bore, better cam etc. Unless you got alot of cheese to blow, I'd ride it stock with maybe a good piston and cam, they go pretty good stock.

[mirror_racing]

well I planned to go with a stroker crank high compression big bore motor with a stage three cam and a port and polished head....

[josborn]

Well then. I'd go big valves too. +1 all the way around. I still think i'd do stainless. I cant tell a difference from ti to stainless, not for mx. maybe for TT or flattrack you might.

[mirror_racing]

I think that is the way im gonna go. it seems like it will do almost as well with ss valves and will have less trouble with them.

[maxamillion]

most valves that where out quickly are due to improper air filter maintenance. not cleaning it enough and or not oiling it properly. if u put a ti valve and a steel valve under the same conditions, obviously the steel valve will out last the ti valve. but its not like the ti valve is going to wear out over night, which is what it sounds like sometimes.

if ur going with a big bore stoker combo, id be willing to bet the cylinder and rings will wear out long before the ti valves wear out (assuming the air filter is taken care of). we are all trying to "free up" these motors to make more power. thats why i like the idea of a light ti valve with lighter spring pressure (less weight and friction) and u dont have to worry about floating a valve. camshaft selection will also affect the life of the valve. some of the really agressive camshafts have steep ramps and are going to close the valve harder. which is going to wear out a valve faster regardless of what material it is made of.

with +1 valves, i can understand why people go with a stainless valve because the price of a aftermarket ti valve is insanely high lol. i would only go +1 if u plan on sending the head to a builder who has alot of time spent on a flow bench that can really take advantage of the +1 valve. you ll have the head sent off anyways to have the seats machined for the bigger valve. then have the carb bored with a nice intake to compliment it all.

in my opinion, save the cash, stick with stock valves which are high quality and fair priced. do a clean up port job which will give you gains and again save a ton of money. and in the end you have a motor that still rips and u just spent a grand less. But when it comes down to it, just go with what will make ur mind at peace! lol thats my 2 cents.

[mirror_racing]

Why didnt u just tell me that Maxie!?! Wait maybe you did lol. Sounds like a great plan buddy! Let's get it started. Just tell me what to order!

[josborn]

The valve seat material in the 02-05 head is a majority of the problem. They changed in the 06- to current head, and it got better.

[FHKracingZ]

On your 06+ TRX motors you can switch to the CRF exhaust valve setup which is +1mm anyways and still have the cheap oem price.