anyone going to use stock repl. valves?

I think I have gotten to about 40-50 hours on my bike. No problems with valves. I just started racing about a year ago so I don't feel like I'm beating my bike like A class riders. I tend to lug the bike around as much as possible. I'd like to repl. some of the more worn parts in my valve train just as a security measure. I'm just tring to figure out my options. I've seen the WMR mods and repl. parts and I'm not too impressed. I was wondering if any of you out there would put stock 2-piece valves back in your motors. I know a lot of you have had problems with these valves and would never use them again. But remember that I am a C class rider that really doesn't hit it as hard as some of you. Let me know. Thanks

We have used the oem valves in ours. Everytime I think about ordering SS they seem to be out of stock. Replace the springs too. Never had a bad failure, they just wear out the coating and won't stay shimmed after that. Still running the original exhaust valves.

When ever you are repl. your valves with the stockers do you regrind the seats?

I replaced my valves with stockers after 6 months of riding 2-3 times a week including races. I also replaced springs, giude seals and keepers. The seats should be machined to ensure they seat properly.

If your not having any problems with your stock valves, stick with them, regrinding the seats is not somthing you have to do every time you replace the valves although it is a good idea to check the valves to make sure they seat correctly, I have never had to regrind any of mine to date and I replace the intakes about once every six months, however if you have it done make sure a reputable place does it or you will be doing it quite often.

Do you check the valves sealing the same way you check with a car head? Just lay the valves in the head and turn it upside down. Fill the combustion chamber with oil and let it sit to see if it leaks out over a period of time? I would think that would show you if it leaking.

i replaced with oem and think that there fine, just make sure to replace the springs, retainers, collots, oil seal and check the chain coz i replaced it due to seeing the wear on the bike and after lining them next to each other realized it was well worn. i tidied the seat with a light dremmel to clear the pits of and then lapped the OLD valves in on the seats to get a nice seal. worked well for me! may aswell do the inlet cam mod while its off!

it was my understanding not to lap titanium valves is this correct?

correct me when i say the dremmel i used the lightest wire attachment available DONT use any of the coarse attachments or grind wheels these will reck the angles of the valves seats, i could use the dremmel on the back of my hand and it didnt hurt so something real light, and yes lapping in the valves on your head will take off the tit coating which is why i stressed use the old ones as there going in the bin anyway. once the seats are lapped in using the fine paste and old valves then just pop your new ones in and your dun! good luck, dont forget the shims are proberly now going to need reshimmin. the titanium is only on the seat of the valves and not the head!

Haven't re-done the seats yet. Checked for leaks with gasoline in the intake port. No seepage. Have re-used the original shimms during both replacements. The seats are very hard, and they don't show wear under a magnifying glass.

Well, after all this consideration and very helpful input, I am going to use a complete stock valve train. I'm calling tomorrow to order it. I'll let everyone know how it went and the results when I get it done. Thanks to all of you for the great input and ideas. :)

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