Uncorking Needle

I picked up the parts to uncork and I am putting it together right now. What position do I put the different needle at? I have seen the stock one change from 2 to 4 but I didnt find an answer to the different needle. Also is there a way to get the muffler gasket from the stock muffler out without ruining it?


Also is there a way to get the muffler gasket from the stock muffler out without ruining it?

Sorry, I'm having a brain fade on the muffler gasket :)

Start out with the 3rd position for the new needle, which is the most common setting.

ok so I got a new needle jet with the needle...stock needle fell out so I dont know which way the new one goes back in...does the longer side go in head first or the shorter side? Is there a difference between the two needle jets or it is jsut packaged with all new needles?

muffler gasket sits inside the muffler wear it connects to the header...a weird fabric type material...same as on my crf 450... Cant figure out how to get it out to swtich it over to the new pipe.

The needle fits in with the tapered end pointing down and the clip is towards the top.

There was a difference between my stock needle and the B53E needle I purchased seperately when I had my stock carb. From what I could tell with my trusty micrometer and a little bit of guesswork, the B53E neelde was approximately two clip positions richer than my stock needle at 1/4 throttle, about one clip richer from 3/8 to 5/8 throttle and the same as the stock needle from 3/4 to full throttle.

I just don't recall removing the muffler gasket even when installing an aftermarket exhaust canister on my brother-in-laws bikes or a friends XR650R that I've worked on, but that was a ways back. I still have the stock exhaust canister with the HRC tip because I couldn't see much of a power gain between it and many other aftermarket exhaust canisters when they were compared in a XR650R pipe shootout a while back and some of the popular brands even lost low end as well as peak power when compared to the stock system with the HRC insert :). I was also concerned about noise and knew CA would be enforcing sound standards at some point in time and now they're here. Being asked to leave the place your riding by the ranger because your bike is too loud ruins the weeked and getting a ticket is even worse. I've never had it happen to me yet, but my son was sound checked on his XR250R while we were out riding, but so was everyone in the group he was riding with and it was all because of one bike in their group that was too loud. Some of the friends I was with a few months back were sound checked and one couple was asked to leave because their bikes were significantly louder than the 96 dba standard, so it kind of put a damper on the weekend. Another thing that shocked me was that the ranger also checked the number on my sons XR250R green sticker off road license to make sure it matched the VIN. He said he usually sends people home if they don't match, but also takes down their info incase there's more to the story than meets the eye.

thanks for the info...got her back together and am waiting on the gasket to show up and then i will slap on the XR's only pipe and fire it up. In bone stock condition I was ok in the regular trails but lacked confidence compared to my crf to take on the big hillclimbs...hopefully now I will feel the muscle and nothing will be bypassed due to lack of confidence in the bike.

Thanks again.

Uncorking her will definitely transform it, but it's quite different than the CRF as you probably already know. Power to weight ratios are pretty similar between the two in terms of peak power, but they're quite different animals. The XR650R is ~55 lbs heaver or so, but you don't feel the weight once it moving, unless of course your on a MX track, or going down steep slow twisty trails or through deep sand at very slow speeds.

Just don't expect to smoke a CRF in a short drag race with a stock uncorked bike, but the CRF will never catch you after the first 20 seconds or so as long as you have the nerve to keep it WOT past 95+ MPH :).

The HP on a stock uncorked XR650R begins to fall off at around ~6,500 RPM (~48 HP) compared to ~8,000 RPM (~40 HP) on a stock CRF. Torque on a stock uncorked XR650R begins to fall off at ~5,500 RPM (~42 lb/ft) compared to ~6,500 RPM (~29.5 lb/ft)on a stock CRF and the final drive gearing is way different between the two. The CRF is an awesome machine for most things, but it will run out of breath before the XR650R will. There's plenty that can be done to boost the XR650R HP into the 60's and torque to around ~50 lb/ft, but as always, performance costs money.

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