CRF 450 Valves
- Thread starter ktm033
- Start date
Web Cam distributes the Kibblewhite SS valves.
Web Cam Inc.
1815 Massachusetts Ave.
Riverside, CA 92507
(909) 369-5144
www.webcamshafts.com
You can check with Powroll www.powroll.com and White Brothers as well
Web Cam Inc.
1815 Massachusetts Ave.
Riverside, CA 92507
(909) 369-5144
www.webcamshafts.com
You can check with Powroll www.powroll.com and White Brothers as well
High Lord Gomer
Poked with Sticks
- Sep 26, 1999
- 11,790
- 34
I poked around and noticed they offer different cams for the CRF. Anybody played with any of these?
Ron Hamp the flat track engine guy apparently helped with at least one of those cam designs. He seems pretty pleased with the results but I don't know any hard facts about the specifics.
I know Hot Cams is also working hard on a CRF450 cam. I'll see if I can get an update from Hot Cams R&D guy Tony Tice.
I know Hot Cams is also working hard on a CRF450 cam. I'll see if I can get an update from Hot Cams R&D guy Tony Tice.
DEANSFASTWAY
LIFETIME SPONSOR
- May 16, 2002
- 1,192
- 0
Ive been using the SS valves with good results Ive been tightening up the intake springs for a bit higher seat pressure . Like .020" You could use Shock valving shims under the lower spring seat if you like. Stainless valves are a bit heavier than stock Ti Never saw a float problem .
mike perry
Sponsoring Member
- May 20, 2002
- 44
- 0
The Black Diamond Valves are more than "a little heavier". They are about 40% heavier. That is why we don't like to sell the valves without the spring kit. I'd rather not sell the valves than have a guy run them with the stock springs. It's not worth fifty bucks to us to have some poor guy scatter his engine.
Rich- What do you hear about the new "black box" for these things? How much higher does it move the limiter?
MP
Rich- What do you hear about the new "black box" for these things? How much higher does it move the limiter?
MP
It's the only aftermarket valve I would put in an engine I built. I have a bunch of YZF4s and even the odd XR or two running around with them, and I've had nothing but a great experience dealing with the company and their products. The longevity compared to oem products is a real step forward that far outweighs the initial cost over the long run.
I was really dissapointed that I had to build Okie's new hot rod YZF262 engine with OEM valves instead of the good stuff. The Kibblwewhite valves weren't available at the time for the 250F but I am pretty sure they are now. Maybe Mike Perry can fill us in with the details.
I'm not much for recommending products because I think most leave a lot to be desired, but the Kibblewhite BlackDiamond valves are the rare exception that I endorse whole heartedly.
For the record I pay the same price as everyone else for their products and get no special deal or treatment, other than getting the chance to bend Mike Perry's ear at the PRI show when I can corner him at the Kibblewhite booth :) Oh yeah, he gave me a couple of free stickers too. :thumb:
Mike - I only have rumors to go on so far but I sent off an e-mail to someone who I believe will verify the specifics. I'll pass along the info ASAP.
BTW, Eric's ISP went bellyup which is the reason for his e-mail woes of late. He should have a new connection early next week. I gave him the basic rundown on the info you asked me to forward to him, and will forward it next week.
He said thanks :thumb:
DEANSFASTWAY
LIFETIME SPONSOR
- May 16, 2002
- 1,192
- 0
Hi Mike : That would probably be a good way to sell the valves : Buy each valve with a spring. What do you think about YZF 400s which originally has steel valves Id like to switch to TI Exh valves and go with the 03 exh cam but am wondering if the 400s stock springs may be too much for the Ti valves and may pound the valves into the seats too hard. Any Ideas on this or should I just buy new 426 springs. Or maybe KW has a set .Its a relatively new 400 motor with very very little time on it if any. If it was really used up Id just buy new springs . I probably should anyway as theyre cheap. I havent yet checked the closed and compressed seat pressures but was wondering if any of you folks have. Any help would be greatly appreciated . Let us know . Thanks DEAN
mike perry
Sponsoring Member
- May 20, 2002
- 44
- 0
In regards to the Yamaha spring question-
The problem of recessed valve faces is 2 fold. #1 seat material vs. ti valve material. #2 not enough spring pressure. As discussed at length previously, ti is soft and doesn't like to be run against a hard seat material. The recession problem is accelerated by insufficient spring pressure allowing the valve to bounce on that hard seat. Running a nickel bronze seat in the head will help, it won't be as brutal on the valve face, particularly in situations where the valve is bouncing on the seat. Adding some spring pressure will also help. Low pressure on a hard seat is a problem.
As near as I can tell there have been 3 generations of intake springs for the 400/426. I'll have to go back and check my notes to see which is which.
I know that some folks are running exhaust springs on everything (In the 5 valve Yamahas) because the exhaust spring has a slightly higher rate. But I don't know off the top of my head which year/model is the best way to go. But, SFO has spent a good deal of time researching the parts history on those heads and has built some. He probably has an answer for what to do until some new designs are available.
We are currently looking at (and have been for a while) all the smaller 5 valve Yamaha stuff. 250, 400, 426, and the 450. Also the R1 and FZR which are now being used in the SCCA "D" sports racer class.
The 5 valve cylinder head package is a challenge. We would like to make a dual spring for it, but, it must fit in a tight package,give a little more pressure than stock, and it has to live at those high rpms. SFO, Eric, and Rich will be among the first to know when we have something that we're satisfied with.
Regards-
Mike
The problem of recessed valve faces is 2 fold. #1 seat material vs. ti valve material. #2 not enough spring pressure. As discussed at length previously, ti is soft and doesn't like to be run against a hard seat material. The recession problem is accelerated by insufficient spring pressure allowing the valve to bounce on that hard seat. Running a nickel bronze seat in the head will help, it won't be as brutal on the valve face, particularly in situations where the valve is bouncing on the seat. Adding some spring pressure will also help. Low pressure on a hard seat is a problem.
As near as I can tell there have been 3 generations of intake springs for the 400/426. I'll have to go back and check my notes to see which is which.
I know that some folks are running exhaust springs on everything (In the 5 valve Yamahas) because the exhaust spring has a slightly higher rate. But I don't know off the top of my head which year/model is the best way to go. But, SFO has spent a good deal of time researching the parts history on those heads and has built some. He probably has an answer for what to do until some new designs are available.
We are currently looking at (and have been for a while) all the smaller 5 valve Yamaha stuff. 250, 400, 426, and the 450. Also the R1 and FZR which are now being used in the SCCA "D" sports racer class.
The 5 valve cylinder head package is a challenge. We would like to make a dual spring for it, but, it must fit in a tight package,give a little more pressure than stock, and it has to live at those high rpms. SFO, Eric, and Rich will be among the first to know when we have something that we're satisfied with.
Regards-
Mike
