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Author Topic: Anybody else running rich down low with dual stage reeds??  (Read 638 times)

Offline RIDE-RED 350r

Anybody else running rich down low with dual stage reeds??
« on: August 21, 2013, 01:56:34 PM »
I have experienced this phenomenon firsthand twice now..

My cousin did a ground-up rebuild on an '87 TRX a couple years ago. It had a Boyesen Rad valve and he replaced the reed petals with brand new. All that thing wanted to do was run rich on the low side. We checked and double checked and triple checked float height and anything else we thought might contribute to this issue. Before he sold it, it ended up being at stock or one size below stock on the pilot jet. I can't remember exactly as it was a couple years back now. Whichever the case it was still too rich down low..

Now the second story the details are more fresh in the ol noggin...

I did a ground-up rebuild on my old '85 ATC this past winter. I still have more to do but that's beside the point right now..

So I wound up with a stock reedcage with dual stage reeds that appeared to be in good working order. This engine has an OEM cylinder with stock porting and bored .050" over. It has simple bolt-ons, PWK36, UNI filter and full FMF exhaust. This engine settled nicely on a 160 main jet, DGH needle on the second groove from the top, but again was way rich down low. I started out with a 48 pilot to make sure it was safely rich and begin the process of working it leaner incrementally. I ended up all the way down to a 35 pilot jet and it still could have stood to lose probably another 2 sizes! Again, double checked float height to make sure fuel level wasn't the cause... But it's spot on....

So, at this point I am getting frustrated.. I mean seriously, already 2 or 3 sizes LEANER that OEM spec on the pilot in a bigger carb, and it's still too rich down low???!!

So, I have other good reedblocks kicking around. I had been running a 1Dir Racing reedblock a couple years ago that gave me no issues other than relatively short reed petal life. I decided to swap the 1Dir cage back in, stepped the pilot back up to a 45 to be safe and whatya know! Still rich but better than the dual stage setup on the 35 pilot jet. Got her trimmed down to a 42 and that seems to be just right. I think I may be able to drop one more size, but I don't know for sure and frankly I don't feel like messing with it right now. It's running much better down low now..

So, I was just wondering how many other people experienced this issue when running dual stage reeds? I had never tried them before this and now I don't plan to ever again. I'll just stick with what works for me.

Also, If anybody has any other suggestions as to the culprit I'm all ears..

Thanks