Well for the past while I have felt my quad had lost some of it's "Magic" that it has been known for. A while ago a freind of mine had something get into his DS cylinder and it scored the cylinder all the way through the nycasil, unless he got it bored it isn't good anymore. Well I decide to check my compression from when my carb had filled with sand as some of you may remember. Sure enough my compression was at 135-140, put some oil in it and it jumped to about 180. As soon as I can I will tear it down and inspect the cylinder, I am hoping that its more the rings than the cylinder. If it is then I can just have the nycasil resurfaced and all would be ok.

Well while i have it tore down I am hoping to do some head porting, install a different piston and was thinking about putting in some HD valve springs. I know Pami, Web, and RWR has Valve springs. My question though is, are they really necassary? I havent heard of anyone breaking the stock springs nor of them floating the valves. Any opinions on this???????

 

i put the piston cams and springs in mine and the springs are a lot better than the stock set up the guy at the shop told me when he took the head apart that the race springs have a better seat set up. and the porting is great it goes a lot better. having two ds's makes it easy to compare. and compare i did my friend with the stage 1 woods was close but not now he can have the hole shot by about a bike or two and third is like see ya. go with springs so you won't have to tear it back apart if you need to put them in later

 

with decompressor disabled, AND throttle held wide open, you should get over 200psi (cranking until no further increase)

 

Scooby I was unaware of the throttle needing to be WO. Why is that necassary? and of course, the decompressor was disabled. Keep in mind I have a stock piston? With it should it still be over 200? Thank you for your help on this.

 

not to step on scoobys toes. You need all your air coming in for those cranks thats why open throttle, if you can force air in (super or turbo) you will increase compresion or charge. more air in more thump.

 

OK, I am curious... a while back I did a comp check at DSmikes and it read 165lbs, W/Wide Open Throttle. What should it be?



Biggerisbetter.

 

KYLE- you do not need any more. The chicken has a hard enough time with you.

 

Prior to significant mods on my DS the compression reading was 185 psi WOT, no compression release. When I disassembled my motor for the build the piston, cylinder, valves and seats were perfect. So I feel pretty confident that 180 to 200 would be in range. But of course altitude comes into play. I am at about 1000 ft. so varying from that, adjustments would have to be made.

 

Mark,

All the chicken needs is some traction and I will be a threat no more. But I am concerned about my compression now. The quad runs fine but ,I would like to know if I may be looseing power or not.



Biggerisbetter.

 

Are you getting blow by causing oil to spew from your vent tube? I didnt till i had real HP with the NOS but i knew my bike just wasnt the same even before I had the nos.