hellomoto

what is the best oil to use in my 06 yz 250f, 06 yz 450f in 60-80 degree weather. i do approx 2 - 20min motos, 2-3 sprints, then practice on corner track for about an hour every day five days a week. we change oil every day and the filter every other day. should i be using a synthetic, blend, or reg, and what weight?

the specific oil is Bel ray thumper racing 4 stroke 20w 50 synthetic oil. this bike has to stay stock for the stock class, but my other bike is getting done with a hinson clutch. motor is being built by PR2. i will measure the clutch springs on Thurs. but we are going to take a new clutch assembly and drill more holes in the basket to try and get more oil, and mill down 5 millimeters on the fingers on the primary driven gear comp. i am told by some engine builders that it will give you 10 lbs of pressure per spring. do you think this oil is too heavy? Thanks for the help!

i am up in Maine and my son is down at the Georgia practice facility so the info i have right now is ............. 1. clutch springs are stock replacement parts 2. no marks on the fingers of the basket 3. oil is bell ray thumper 20w-50 the answers to 4,5,6 i do not know right now but i am going down to Georgia this week and the person that has been doing the work on the bike is a full time Honda mechanic for a race team but helping us out. we have drilled 8 more holes in the clutch basket to see if that would help and it seemed to last a little longer. each time we do the clutch we change the springs, fibers, and steels. the reduced power issue is it just seems to have less power all over then when we first got the bike but this is from my son talking to me over the phone . again i will get more info later next week. i am not BSing on any of this so thanks for any and all info. i posted on this sight because the Yamaha cust service said to bring the bike to the nearest Yamaha dealer. but i do not like to bring my race bikes to a dealer. there is going to be a yamaha trailer down there this week so i will have them look at the bike then. THANKS FOR THE HELP!

i have an 06 yz250f down at gpf training facility. and have gone through 4 clutches in 30 hours of practice. had 250's, 125's, and 80,s for years and never had to replace clutches. also bike has reduced power and the valves have been adjusted twice, and new piston and rings. use bell ray thumper oil changed every couple of hours. any suggestions????