IMPORTANT aftermarket exhaust question.

I just installed a full FMF 4.1 system and mega bomb header on my 08 wr450f and it took a good many kicks before it fired up. Once it did it there was a small bit of coolant on the floor. All hoses are on tightly and no cuts in them. The bike is like brand new so theres noe hose issue. However in the casing for the water pump i noticed a tapped out screw hole. This seemed to be the place where the coolant was coming from. It was only a small drip form not flowing out. Once i shut the bike off there was a burning smell from the header, midpipe and muffler( Possibly where its new?) I also herd the coolant in the rad bubble. What could possibly be the problem?

did you rejet to compensate for the aftermarket pipe?

That hole is the weep hole for the water pump, when it really leaks the pump is bad. Depending how long you let it idle the overflow will get some coolant as there is no fan on this bike. They seem to get warmer fast sitting still. Also you might want to go alittle fatter on your jetting.

Being that it's a new bike I think the coolant drip will go away when the water pump shaft wears into the seals. If it doesn't stop, change the seals, it's not too difficult to do. It's normal for the header to have a funny smell to it when it's new. It will also smell like burned when your hands touch it and leave oily residues. Don't leave idling for too long, these bikes overheat if they stand still idling for more than a couple minutes. Rejetting wouldn't be a bad idea after installing the exhaust, stock jetting will definitely be way off with that exhaust.

the bike prolly as 2000kms on it of all street use, its a motard. I've never seen it leak before. but like i said before it was a very very small amount.Also the bike has the gytr ASI removal kit in it. it has a 172 main 3 position needle and whatever else was in the kit. I thought the 172 would be good. It ran fine with the stock system(bit rich if anything) with the insert removed. Cant ride it yet due to snow coverd roads.

OK, The bike Runs really well with current jetting. Only problem is, coolant leaks for a bit at start and then it stops. Still an averange amount left in the overflow. Also it takes A LOT OF KICKS to start. I dont know if this is due to the battery being stone dead and old gas but after it finally fires up, I have no problems kicking it over again. What jet do you replace for better fire up, the pilot?

Charge up the battery.Try giving it a few squirts of fuel using the accelerator pump in the carb.It should start easier then.

I'm sure it must be pretty cold still in Newfoundland like here in BC. For cold starting when it's cold out, lean your bike over untill fuel starts flowing out of the carb overflow tubes. A couple squirts of the throttle and she'll fire on the first our second kick.

Your pilot effects starting. The GYTR 50 pilot is way too rich. I run a 45 pilot(stock)

YZ exhaust, 1000-5000' elevation.

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