Ok here goes. I just bored over .20 wiseco with 10 1/4 comp. Added stage 2 hot cams and all kibblewhite valeves and springs. Had a shop do all honing and valve stuff. After i put all back together having questions. First i ran for a couple minutes the header turned red. So its lean. Put a bigger pilot jet in no problem now. 2 things. The head gets so damn hot at idle and reving its untouchable. Just seems a little to hot to me. Its getting oil and the oil wasnt. Burnt or boiling. I did just let it idle for about 10 minutes and it got to a cert temp and thats was it didnt keep rising, still untouchable. I was thinknig cause of compression??????. Not sure if its normal. Also the dam valve adjusters tick pretty loud. I checked lash twice and dead on. So please can someone tell me if this is normal im gettin worried.
new rebuild need help!!!!!
- Thread starter tony1177
- Start date
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I don't know if you ever touched your head before you did your rebuild, but i'd be willing to bet it was nearly as hot then as it is now. I never encountered any engine, especially an air cooled one, that the head didn't get too hot to touch. Normal operating temps for air cooled engines can get to over 300 degrees. The additional compression will cause an increase in temperature, I had the same piston and it it did seem to run a little hotter, not to the level that it was a problem in any way though. Just a little hot on the legs in the summer.
These engines are naturally ticky and generally noisy because they have 2 large valves, most modern powerplants this size have 4 smaller valves. Adding a more aggressive cam will definitely make the ticking much more noticable. As long as you're sure you have the lash set correctly you don't have anything to worry about. Just keep an eye on it for any changes, if it seems like it gets louder or changes in sound then you would want to look into it further of course.
These engines are naturally ticky and generally noisy because they have 2 large valves, most modern powerplants this size have 4 smaller valves. Adding a more aggressive cam will definitely make the ticking much more noticable. As long as you're sure you have the lash set correctly you don't have anything to worry about. Just keep an eye on it for any changes, if it seems like it gets louder or changes in sound then you would want to look into it further of course.
jasonp
Well-Known Member
tony1177 said:
Yeah it is going to get hot! Just like stock letting your warrior with an air cooled engine is going to get hot just sitting there idling. Really you shouldn't let it idle for that long anyway if you are breaking in a new cam and piston.
Personally I would take the hotcam out and put a Megacycle or Web as there ment for HD valve springs and have better lift and durtation numbers.
Have you taken your bike for a ride yet, it doesn't do anything wierd on the 0-1/4 throttle does it? Just want to make sure it is not still lean on the pilot.
DeadLastRacing
Well-Known Member
I was in the same boat.....though my was running really really hot after the rebuild and it was and yeah it will be fine. Think about/look into doing and oil cooler mod.
thanks guys. yea i took it this weekend for a long good ride. its mean up high in rpms. ripppss. but my pilot jet is too rich. i went to yamaha to get a bigger one than stock but they didnt have thr right kind so the one they gave me was super rich. what u guy run for pilot and main????? would help with tuning. will look at other cam though but this one does rip up high.
sykowarrior357
Active Member
i used a 150 i think, 152.5 for a little while but was too rich for me, now i use a DJ148 i think...
A DJ 148 would be insanely rich, that's over 170 in mikuni sizing.
The cam and valves shouldn't affect the jetting much, the piston shouldn't either, the big contributing factors are going to be the intake and exhaust setting you're running. Are you running open airbox, drop in filter with lid, what kind of exhaust? You should be somewhere in the range of a 147.5 to a 152.5 main, and just one step up from the stock pilot (I forget what the stock one is, maybe 40) should be pretty good.
The cam and valves shouldn't affect the jetting much, the piston shouldn't either, the big contributing factors are going to be the intake and exhaust setting you're running. Are you running open airbox, drop in filter with lid, what kind of exhaust? You should be somewhere in the range of a 147.5 to a 152.5 main, and just one step up from the stock pilot (I forget what the stock one is, maybe 40) should be pretty good.
sykowarrior357
Active Member
runs great with DJ148 no fouling, starts easy, revs good, and its also what the Dyno-jet guide says for me to use at my elevation with the lid off.
yea sorry took so long to respond. well went again. its pig rich. from 1/8 to 3/4 throttle its poppin when ur in it. the yamaha dealer gave me a pliot jet but it has holes all around the sides and is not the right one. its a 20 and still too big. i have a 150 in main could be a little bigger. i have the jet needle i think 1 notch richer than the middle. any help would solve this little prob
sykowarrior357
Active Member
imo the needle clip seems like it would be better off in the stock position which is right in the middle.
bomber315
Well-Known Member
charles said:
explain this?!???
I would keep checking the hotcam for wear, they are designed for stock springs normally. Whenever you first idle a newly built motor for the first 10 or so minutes for cam break in you'll want to put a good fan on the top end, they always run hot until fully broken in. I would definately do the oil cooler mod if I were you, it's very cheap and cools things down dramatically depending on the cooler you use. If you remember going through puddles with the stock components the motor boils water instantly that hit it, so not being able to touch it is normal, they always run hot compared to liquid cooled. Keep in mind that if you keep the oil 20 degrees cooler you can almost double the components life, so a oil cooler is a big plus.
