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I lost 4-5 oz in the h/s race this w/e. I beleive I smell it but can't find a leak spot.

Little history, just had valves replaced and wasn't losing fluid before this. Not sure if I should have bled the radiator?

Also before this started I couldn't start bike and messed a little with the fuel screw, put back where previous owner told me to, so could be lean, but seems to run and start fine.

Any ideas or known problems with the R. Leak and above work could be a coindedence?!

If your loosing water you should see it somewhere on the bike, burned white coolant on the engine Etc, unless its just pumping out the overflow, HS's are hard on the 450r's in hot weather. I raced one last year but had plenty of long staight aways to cool it down, still lost a little. I'd flush it with bottled water and then fill it with some new coolant. If its still loosing a lot check your waterpump seal and try a new radiator cap. Engine Ice works well in the thumpers.

i agree you should be able to see it unless it's a head gasket. don't forget to check the weep hole at the water pump. it's very unlikely that much water would be lost there but possible. i'm assuming you have checked the oil and they don't look like chocolate milk?

ken

crfsonly wrote:i agree you should be able to see it unless it's a head gasket. don't forget to check the weep hole at the water pump. it's very unlikely that much water would be lost there but possible. i'm assuming you have checked the oil and they don't look like chocolate milk?

ken

So far oil is fine. How would you check a head gasket for leaks? Remember just got her back from valve replacement. I don't see anything coming out the weep hole and the over flow appears dry.

Thanks for some info.

Pops

if it's a blown head gasket then coolant may be passing into the cylinder and burning with fuel. one way of detecting this is performing a leak down compression test. this requires a special tool which you likely don't have. however, if there is no external loss of coolant the only answer is internal loss and if it's not in your oil then it is likely burning in the cylinder.

ken

crfsonly wrote:if it's a blown head gasket then coolant may be passing into the cylinder and burning with fuel. one way of detecting this is performing a leak down compression test. this requires a special tool which you likely don't have. however, if there is no external loss of coolant the only answer is internal loss and if it's not in your oil then it is likely burning in the cylinder.

ken

Turns out you were right. The water was going into the cylinder and finally starting leaking externally.
Turns out the head wasn't torqued tight enough.

Thanks for the help!