'89 Jetting issues, want to know if I'm doing this right

Got questions? We got answers....
Post Reply
KDXrider1989
Member
Posts: 643
Joined: 09:05 pm Sep 07 2010
Country:
Location: Houston, TX

'89 Jetting issues, want to know if I'm doing this right

Post by KDXrider1989 »

I messed with my carb a while back when I got my FMF pipe and boyesen reeds, and it seems like my bike is running rich since then, or richer. It smokes a bit and just feels a little down on power, so I opened up the carb yesterday. Still found the 45 pilot and 155 main (I live near sea level and temps in the 90's), but I noticed with the carb upside down it measured about 14.5mm from the float bowl mating surface to the top of the float. It states in my manuel that it's supposed to measure 16mm, so I corrected it and ran the bike and now it feels like it's running lean, or is it that the bike is actually running better and I'm not used to the power? The exhaust smells a little different too. Followed the jetting guide on here and I'm at 1 turn out on the air screw, when I used to be about 2. I guess my real question here is: could a 2mm difference in float adjustment screw up the motor?
User avatar
KDXGarage
KDXRider.net
KDXRider.net
Posts: 14047
Joined: 06:45 am Nov 01 2004
Country: United States of America
Location: AL, USA
Contact:

'89 Jetting issues, want to know if I'm doing this right

Post by KDXGarage »

I am no jetting master, but if it says 16mm, then it HAS to be 16mm. Any tuning should be done after that is done. I am just thinking, any tuing you did before was somewhat compensating for the level being off (or if it went off, then it threw it all off).
Thank you for participating on kdxrider.net. :bravo:
To post pictures from a device: viewtopic.php?f=88&t=24128
User avatar
SS109
KDXRider.net
KDXRider.net
Posts: 5770
Joined: 05:11 am Aug 23 2009
Country: USA
Location: Tucson, AZ, USA
Contact:

'89 Jetting issues, want to know if I'm doing this right

Post by SS109 »

I agree with Jason. You got to have your float level set right first and then you can start messing with your jetting. Follow the jetting guide to get it spot on.
Youtube Channel: WildAzzRacing
AZ State Parks & Trails OHV Ambassador - Trail Riders of Southern AZ
Current KDX: '98 KDX220
Old KDX: '90 KDX200 -White/Blue
'11 GasGas EC250R
KDXrider1989
Member
Posts: 643
Joined: 09:05 pm Sep 07 2010
Country:
Location: Houston, TX

'89 Jetting issues, want to know if I'm doing this right

Post by KDXrider1989 »

Agreed, that was with the tang not bent at all, had to bend it to get to the factory 16mm level which I thought was kinda weird, unless the floats were bent :hmm: I measured from both sides of the float and they were both at 16mm. This may be a dumb question to ask, but in the case of bent floats, would 16mm from the flat surface to the top still be OK since its 16mm?
MikeyMike
Member
Posts: 15
Joined: 10:27 pm Jun 09 2012
Country:
Location: Huntsville, AL

Re: '89 Jetting issues, want to know if I'm doing this right

Post by MikeyMike »

Where'd you get the headlight?
KDXrider1989
Member
Posts: 643
Joined: 09:05 pm Sep 07 2010
Country:
Location: Houston, TX

Re: '89 Jetting issues, want to know if I'm doing this right

Post by KDXrider1989 »

MikeyMike wrote:Where'd you get the headlight?
It's a UFO Twins, got it used for a very good deal on ebay
Post Reply