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renegade805
05-03-2011, 04:54 PM
05 cr85 142/48 nfsf needle 3rd clip stock motor reeds and pipe. 15/48 gearing airscrew 1-1/2 2x6 pod filter. Going crazy can't figure why it's sluggish low and mid. Even pinned in mid it takes time for power to kick in.any help would be greatly appreciated I might even throw in a 6 pack if I don't finish it first just got to wall away oh btw don't have the room for 6 th gear plug chop.I don't think I'm lean

renegade805
05-03-2011, 04:57 PM
Sorry central Jersey 28 pwk d slide

renegade805
05-04-2011, 06:07 AM
Plug looks good little rich. I'm thinking it might be needle.is there a different needle people ate running. Might raise clip to lean out mid

renegade805
05-04-2011, 05:37 PM
Bump just checking

FISH ON!
05-04-2011, 05:48 PM
I found the Honda service manual to be real good for jetting the stock motor. I'm no expert by any means but I'll tell you what I think you should try based on my experience and what the manual states for that year and your elevation in Jersey...............

I would go back to stock settings which should be slightly rich and then tweak it from there. Here's a copy of the chart. I've circled the area I think you should start with then try leaning out the slow jet one size if the problem continues. If you get to far off the chart you have something else going on. Between this and changing the gearing you should be as good as it is going to get. Then you get into the mods to build bottom end power. We went with a DEP pipe that helped a bit.

Hope this helps............

http://i37.photobucket.com/albums/e57/striperfishn/CR85jetting001.jpg

WISH1965
10-14-2011, 05:22 AM
What heat range of the plug do you all recommend? 7, 8, 9, 10??

renegade805
10-14-2011, 05:40 AM
I run a 10 no problems

WISH1965
10-14-2011, 07:29 AM
yeah i think ten is what Honda recommends from the factory for the CR85, was curious what other guys use.

Hetrick Racing
11-17-2011, 06:43 AM
The cr engine is not really going to have a bunch of bottom or mid.
Growing up through the Elsinore days it by no means is that bad but still lacks down low.
Jetting wise I would run about a 138 main with a 45 pilot is the norm on my dyno(stock motor).
I am at 1250 feet though so a 140 may be better in Jersey.
We have always ran an 8 plug usually a br8eix
Are you running flat track? if not your gearing is off IMO we run a 14 48-49-50 at most national tracks sometimes a 15 51(which is close to the 14-48)
With a stock motor more gear will help your issue.

WISH1965
11-17-2011, 07:40 AM
Not sure who you are replying to, but some of the numbers you provided us as well as others were real close. Tuning our CR85 stock with Keihen 28MM & a DEP pipe was real easy to get it close. I could probably fine tune it, but it was real good initially. SJ 45, MJ 145, #3 on the needle clip. Gear 15/50 MX racing. BR8 plug is what i left in it. All those factors & our plug was a nice chocolate color. Thanks for you input.