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craftsman13

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About craftsman13

  • Rank
    TT Bronze Member

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  • Gender
    Male
  • Location
    California
  • Interests
    2 Wheels, Guns, 4Wheeling
  1. craftsman13

    Help with 40mm FCR jetting and poor mpgs

    Thanks for the recommendations Dot-com, I will deffinately give it a shot. By the way I'm at sea level. I have the carb on the bench so I can set it up in one shot. I will also check the float height, which was good when I cleaned the carb. In regards to the off idle bog, it didnt start doing that until I went with a smaller main jet (from 155). Maybe I was too lean? Ill post back here with your recommended setup as soon as I get it put back on the bike and do a mileage test. I may wait until I get back from my trip so I dont put uneccesary miles on my tires. Thanks for everyones input.
  2. craftsman13

    Help with 40mm FCR jetting and poor mpgs

    I actually I threw it on last night and went for a ride to check my mileage and I'm getting 44 mpg with Daves mods and 55/158 jetting. I was getting this before the swap. I do have full knobbies on right now, the engine is fresh with 1,500 miles, the bike is kind of stripped down (lighter), the altitude varies from sea level up to 2,200 feet, and not much wind here this time of the year. I'm using the the CRF cables and throttle assembly which has a small amount of twist compared to the XRL throttle assembly, so I'm wondering if with that short amount of action is making the carb use more fuel. What I'm saying is there isn't as much control with the CRF throttle assembly compared the the XRL.
  3. craftsman13

    Help with 40mm FCR jetting and poor mpgs

    Alright, so I put roughly 50 miles and did an mpg check Im getting 32 miles per gallon. I did a plug reading and Im slightly lean but it runs really good but it still has a bog/miss at 1/8 throttle. Maybe the AP pump isnt timed? Im open to suggestions if anyone has any. Im going to Death Valley in 2 weeks so if I cant sort this out Im going back to the CV carb pretty quick here.
  4. craftsman13

    Help with 40mm FCR jetting and poor mpgs

    Its my understanding that the pilot jet is the jet to get sorted out first. This is the jet thats going to let the engine start and idle correctly and if you cant get that, then you cant find the right main jet.
  5. craftsman13

    Help with 40mm FCR jetting and poor mpgs

    This bike spends 90% of the time in the dirt, right now I'm using the street for tuning purposes. I think your right, I'm going to have to mess with the needle to really dial it in. Thanks for the recommendation. I need to do a full throttle test and plug reading to find the right main jet.
  6. craftsman13

    Help with 40mm FCR jetting and poor mpgs

    Alright sorry for the late reply, I was in the middle of moving and fixing up my new home. Anyways I swapped out the leak jet for a #35 from a #70 and also reduced my main jet to a #152. While I had the float bowl off I figured I would check the AP pump diaphragm to make sure I installed it correctly and to my surprise it was installed upside down. So I flipped it over and reassembled. I took the bike out and rode 81 miles with varying roads from highway to twisties and I only managed to get 30 mpgs. I noticed that toward the end of my ride it started to hesitate at 0-1/8 throttle and when I pulled the plug it was really black and sooty. This is why it started acting up I'm assuming. So I think the #35 leak jet is too much so I went up to a #70 leak jet to reduce the squirt. I also went down to a #150 main jet to help the already rich condition I had before swapping the leak jet. I took it out for a couple of miles around the neighborhood and it feels like it has the most power I have felt yet especially mid to high rpms. I'm going to try and take it out tonight and put 50 miles on it to see where I'm at. I'm also going to pull the sparkplug before I leave and see what it looks like from the short ride I took it on. I'll post back after I do a mileage check and sparkplug reading.
  7. craftsman13

    Help with 40mm FCR jetting and poor mpgs

    I think you are right. Heres a link i found on youtube showing 70, 35, and a blank leak jet. They have different durations too.
  8. craftsman13

    Help with 40mm FCR jetting and poor mpgs

    I dont have a sumo setup, but good point. Ill test it this weekend with a gps.
  9. craftsman13

    Help with 40mm FCR jetting and poor mpgs

    I wonder if the 70 leak jet is a contributed to the poor fuel economy? I think my main jet has to be too big considering it being mostly highway miles with the throttle open as much as it is. Smaller jets are ordered by the way.
  10. So I gave up on the CV carb and installed a 40mm FCR-MX carb off of a 2007 CRF250R and got the jetting really close, atleast it feels close. I haven't done a plug reading but the bike doesn't bog at all, doesn't blow black smoke and pulls really strong.I am only getting 29 mpgs with mostly highway and some spirited riding and I think that is really low considering what I have heard others are getting and the stock carb always got me 44 mpg. Do you guys think I'm jetted to rich (I must be right), I pretty much copied DotComs jetting but leaned out the pilot and main jet one size. I figured out my pilot was too rich from turning the air/fuels screw all the way in and the bike would still run so now with the smaller pilot I was able to set the A/F screw to 2 turns out. My jetting is as follows; NCVT needle 3rd clip from top 40 pilot jet 155 main jet 100 slow air jet (stock) N/A main air jet 68 starter jet (stock) 70 leak jet (stock) The engine and exhaust is mostly stock with stock header and muffler, Uni air filter with some small holes drilled in the air box, stock cam, and a 102mm JE piston at 9.6:1 compression (XR600R 10.8:1 piston installed) Tell me what you guys think. I am planning on buying more jets tonight including a 35 leak jet and leaner main jets. Thanks
  11. craftsman13

    FCR-40MX Carb - Awesome Upgrade

    Thanks for the replies. There is no main jet on the carb I have, i hope tuning wont be difficult. I also picked up a NCVT needle and am waiting for some jets and seals in the mail. I think for a starting point i am going to go with; NCVT needle w/ clip on the 3rd groove from the bottom 158 main jet 42 slow jet 68 starter jet 100 slow air jet 70 leak jet These are the jets that came in the carb except the main jet so we'll see how it works out. If anyone has any suggestions feel free to throw them out there.
  12. craftsman13

    FCR-40MX Carb - Awesome Upgrade

    I picked up an FCR carb recently and im not sure if its a 40mm or 41. I measured the inside diameter on the inlet side on the carb and it measured 41mm. Does the throat taper down? Which way should I measure it? The seller said it came from a 2007 CRF250R which tells me its a 40mm. The main air jet is non adjustable if that matters. Here are some pics.
  13. craftsman13

    First 2T 2000 CR250R

    I got my sprockets and chain 13/51 114 link and the chain is too tight. Do any of you see a problem with removing the locknuts on the bolts so the bolt can go in the swingarm a little more?I only need a little bit more and with the pressure on the bolt I don't see it loosening up.
  14. craftsman13

    What year CR250R for a tall rider

    Thanks CamP this information is really helpful
  15. craftsman13

    First 2T 2000 CR250R

    250Rider, I live in Half Moon Bay so all the local riding parks are no that far. I know the front forks had a recent oil change but I think that was all that was done so I'm going to do some research and upgrade the springs and some other bits. The rear shock hasn't been touched ever so it's time to get in there and replace some seals, oil and charge it, I would like to keep the reliability so Im going to stick with oem parts. I haven't looked on any parts fiche so I wasn't sure if you could by the parts separately, do you have any recommendations for mandatory replacement parts in the shock? I've heard good things about the NoToil biodegradable foam filter oil, I will be trying that as soon as I run out of my UNI filter oil. I came back from a 1,200 mile trip in Baja which was about 80% sand and dirt and the filter did great so that says something about the UNI filter and Oil. YHGeorge, thanks for mentioning the checking the linkages I am going to look at them next chance I get and regrease or replace the bearings. Have any of you drilled and tapped some of the suspension parts for Zerk fittings to keep the suspension greased easily? Here are some pics of the bike as it sits now. The chain and sprockets will be here today!
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