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R&D power pump +Jd jetting

2822 Views 6 Replies 4 Participants Last post by  Badprimer
Hey Guys/Gals
Question for ya, I had my local dealer install the jd-jetting on the 525xc. Quad runs great! Well I also had ordered the bolt on R&D power pump. What I'm wondering is .... If my carb is properly jetted right now, will I have to re-jet it after I install the power pump? And if so, will I have to change all the jets or just certain ones? If your pretty keen on this please list which jets to alter and from what size difference.
Ty for you Help,
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Well I installed the power pump today and things did not go as planned. Quad cuts out if I hit the throttle quickly. I called R&D and I must say I was very pleased with the customer service. R&D said I should get a bigger pilot jet, so that's what I'll try tomorrow and if it works I'll reply and let you know what jet size I used to make it work.
If anyone else is using JD jet kit+ R&D bolt on power pump on the 525xc maybe you can tell me what size jets you used and save me some time. If not I'll give an update tomorrow.
Any updates?
I've taken my carb apart so many times lol I figured I wait till i got all my parts so I could limit the work. I've been waiting on a spring to reduce the thumb throttle stress and I finally got it today. Tomorrow I got an eye exam and I'll have my eyes dilated so depends on when they go back to normal if I'll finish the carb tomorrow, if not I'll do it Saturday and post the results.
Ok guys here we go..
Using JD jetting I went with blue needle 2nd notch from top.
172 main jet
52 pilot jet (it had a 42 and I don't know if shop had changed that or it was factory but without the power pump 42 worked just fine)
The R&D power pump had a stronger spring to change out but for the life of me I could not get it to work. The plastic shaft that the spring sits on is shorter than the new spring so the last loop of the spring wants to sit under the plastic shaft, it may be possible to use the spring if you have 2 people helping to keep the spring compressed as its installed. Luckily the Jd jet kit comes with an o-ring that works in a way that makes the stock spring stronger so after a lot of frustration I went with the stock spring.
I also installed a fuel mix screw that sits just below the bottom of the carb and I have the mix screw 2 turns out. I also have the power pump 2 turns out. It runs pretty damn good but I think I could even get it finer tuned but its so close I probably won't bother.

I also got the throttle reduce spring from http://www.tokyomods.com/honda/99-06%20CRF250%20RX.html

I had to modify the spring a little, on the spring there is a short end and a longer end. I clipped the longer end off and re bent it to the same shape. If you do the same mod just try to get it close as you can to the stock spring and it has a much better fit.
I used a fish scale to measure the pull and I'm sure the accuracy is going to be way off but you can still see the results.
Stock pull was right at 2lbs and after modified it was 1lbs. I have not taken it out on a ride other than just up my street to test the jetting so I'm not sure if after a long ride if there will still be thumb strain but I would bet that even if the scale was not accurate it did have half the pull and it did not seem to soft as the carb still worked like it should.
products rated
JD Jet kit 10/10
power pump (no rating because I'm on the fence if this did anything)
thumb spring 7/10 (spring needed modified)

Hope this helps you decide what will work best for you,
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james dean recommended my jetting as follows:

#45 pilot jet
1 1/2 turns out on the fuel screw
Red marked needle in the #5 from top clip position
#185 main jet
Float bowl screw for accelerator pump set at 1 1/4 turns out from lightly seated

i also have the r&d powerpump which came with my r&d powerbowl. i will let you know how it all turns out...
Hi guys. New in here! Great forum, great info. Not yet a KTM owner, but who knows.. maybe one day :)
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