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Everything posted by Red_250X

  1. Just wanted to give you X fans some real world successful jetting settings. I just got back from a trip to Colorado and wanted to share these settings. Our camp was at 6100' and we rode up to 13,000'. Temperature was between 65 and 85 (absolutely PERFECT!). Modifications: Airbox opened about a third of CCC recommendations. Baffle removed, but spark arrester in place. Pilot jet changed from 40 to 42. Setup: -Needle in stock position -Main jet - 142 -Air screw at stock position (I probably could have made some improvement, but I was having too much fun riding and I didn't experience any hesitation) The bike ran great and climbed some HUGE hills. Most of our riding was single track, switchbacks, very difficult and technical - a lot of 1st and 2nd gear. NOTE!! Apparently, the 250X is jetted lean in stock form. Opening the airbox and removing the baffle leans the carb even further. IF YOU DO THESE MODS, REJET YOUR CARB!!! Otherwise you could do serious damage to the motor. It will run significantly cooler when it is not lean. I live at about 600' and am running a 152 main jet.
  2. Red_250X

    Woods gearing on 250X???

    I dropped one tooth on the front sprocket (12) since I do a lot of technical riding. I've only topped it out a few times...it's a good compromise for me and I don't have to abuse the clutch as much.
  3. Red_250X

    Any big guys on the 250X??

    6' and 225 lbs. It works GREAT for me...even at 13,000'!
  4. Red_250X

    Is there such a thing as TO cool?

    The premise that these manufacturers are working under is that they are providing a liquid that transfers (conducts) heat better. You want the liquid to absorb more heat in the engine, and then transfer that heat to the cooling fins in the radiators. They aren't just using more antifreeze. As a matter of fact, with normal antifreeze, using straight antifreeze will not cool as well as using a 50/50 mix with water. One of the things that I like is that they already pre-mix it with deionized water and come up with a product that has a high boiling point, a low freeze point, enough lubrication for the water pump, and transfers heat well. I use Water Wetter in my truck and can actually tell a difference. Before using it, the motor would "ping" under a load in the summer with the AC on. After adding Water Wetter (2 bottles for the large cooling system), I can only get it to "ping" occasionally. That was enough to convince me that they were on to something. If I were wealthy enough, I'd run Engine Ice in my truck. A high performance bike is more susceptable to heat, and it only takes half a bottle to fill it up, I spend the extra bucks. Same goes for the oil...I use the Honda HP4 w/ Molly in the engine, because it takes less that a quart for a change. $6 for an oil change is acceptable to me. Just my 2 cents worth.
  5. Red_250X

    Need 05 CRF250R Spark Plug

    I bought a couple of spares for my bike and the guy behind the counter said the total was $21!! After further checking, these bikes have some kind of an esoteric, new plug that's very hard to find anywhere but at a Honda shop.
  6. Red_250X

    Is there such a thing as TO cool?

    There is such a thing as running too cool, but you'll never get there unless you're riding somewhere below 0 degrees F. Use all means possible to keep things cool...it helps. Another way that the better cooling systems (i.e. boysen, engine ice, fans, etc.) will help is by smoothing out hot spots in the engine. A hot spot on your engine head can cause pinging...bad...very, very bad!
  7. Red_250X

    Jetting Settings

    What mods have you done to the exhaust or air box?
  8. Red_250X

    Jetting Settings

    I removed the backfire screen (bent a few metal tabs and retained the plastic frame). The bike has A LOT more bottom end. I'm going to try a richer main jet next weekend. I think that removing backfire screen leaned out the carb and I can probably obtain even greater results by going richer.
  9. Red_250X

    Anyone have a powernow for sale?

    Save yourself some bucks and increase performance. Buy the SLP Power pak instead. You can get it from Dennis Kirk products or the factory at http://www.startinglineproducts.com. It works great!
  10. To change the jets, you can loosen the rubber mounts (on the engine side AND the airbox side). Remove the 17mm cover on the bottom of the carb. Tilt the carb, so you can see the jet. Remove and replace. I can change jets in about 15 minutes now.
  11. Red_250X

    Jetting Settings

    Here's a great site for jetting information. It references the Yamaha high end four strokes, but it's the same carb as we have on the CRF250's (and probably CRF450). http://www.thumperfaq.com/jetting.htm
  12. Red_250X

    Maximum Rear Tire size

    Anyone have any experience with a rear tire larger than 110/100-18? I want the largest tire possible.
  13. Red_250X

    Maximum Rear Tire size

    You're exactly right Optik. If you don't believe me, mount one and see...I've done it many times. The outside knobs don't move that much with different rim sizes. Take a new tire (not mounted) and sqeeze the inside to various width's to simulate different rim sizes. Even though it will be a little different when inflated, the difference is very similar.
  14. Red_250X

    Jetting Settings

    You're probably a little rich if the baffle is still in. At the same altitude in CO, I ran a 130 main and 42 pilot with the baffle out and the mods listed below. I could hardly tell a difference in power. Out of the 25 bikes in our group, the only ones that could outrun me were an XR650 and a WR450F. I climbed some hellacious hills...the only problem I had was just hangin' on!!
  15. Red_250X

    my oil choice

    Changing oil often is definitely good, but changing synthetic oil often is even better! The synthetic oil has better lubricating qualities and reduces heat (especially the moly version which can only be used in the engine compartment).
  16. Red_250X

    Maximum Rear Tire size

    Some of us are actually engineers and understand the laws of physics and how they apply to engines, the drivetrain, and tires. Any engine builder that believes what you're telling us, isn't worth his weight in salt. Let me explain this so even you can understand. A taller tire will "gear up" (less power, more speed) a vehicle. Here we are talking about a 1" maximum difference on a 26" tire. That equates to a 3.7% change in gearing...very minimal...and that's the MAXIMUM difference. Now, a wider tire. If we assume that a wider tire is heavier (it may or may not be depending on the construction), we are talking about a maximum difference of about 4% (maybe 6 oz). Now, since the overwhelming majority of the load in placed on the engine by it's attempt to move the weight of the bike (245 lbs, with a few aftermarket add-ons) plus the weight of the rider (200 lbs) which equals 445 lbs, the effects of a 3.7% gear change and/or a difference of 6 oz on the tire is VERY minimal. Now, we could get into torque, rotational velocity, centrifugal force, gyroscope effect, etc., but none of this is significant with the types of changes that I'm talking about, and you probably wouldn't understand it anyway. As far as how the bike handles, you will tell more difference due to the construction of different tires (4 ply vs 6 ply, sidewall stiffness, rubber compound, tread design, etc.) than you will the difference in size unless you go to extremes. Now, here's where you may have a point. The larger tire will have a larger contact area, therefore better traction, therefore the tire will "hook up" better and spin less, therefore loading the engine more, therefore improving the acceleration of the motorcycle and rider, WHICH IS EXACTLY WHAT I WANT!!!!! There would be less of a load change on the engine in going to a larger tire, than there would be in the change from a 190 lb rider to a 200 lb rider, or even in having significant amounts of mud stuck to the bike. The analogy of the big truck tires that are 300% to 500% larger than stock is a poor comparison. We're talking small changes here!!! Please, if you want to show your ignorance, that's one thing, but don't mislead these people who may not know that YOU don't know what you're talking about.
  17. Red_250X

    Works Connection radiator guards

    The louvers do provide a LOT more air into the radiator. Here's a link to a guy who modified his louvers to work with a "wrap-around" style radiator guard. I think this would be a good compromise. The radiator mod is near the bottom of the page. http://www.rickramsey.net/CRF250Xmoremods.htm Manufacturers should pick up on this and give us something off the shelf for this problem. Another benefit to the louvers is that they almost eliminate the possibility of mud getting the radiator. I was surprised to find the radiators were spotless after one of my REALLY muddy rides.
  18. Red_250X

    Maximum Rear Tire size

    I can't imagine anyone thinking that a wider tire would actually slow the bike down significantly. This bike has power to spare!!! I've always run large tires on my bikes. I had a 120/100-18 on my XR250 and it worked great. As for the reasoning, I ride on a lot of different types of terrain. I need additional traction on mud, snow and sand.
  19. Red_250X

    Anyone had clutch problems?

    I used Castrol 20w-50 in the tranny one time and the clutch wanted to drag when disengaged. I went back to Honda HP4 as soon as possible (after 200 miles) and the problem went away.
  20. Red_250X

    questions about high compression pistons

    The X comes with a high compression piston.
  21. Red_250X

    Received a phone call from American Honda today

    Engine Ice and synthetic or synthetic blend in the crankcase definitely help.
  22. Red_250X

    Tall seat foam for X?

    They have foam and cover.
  23. Red_250X

    Am I to big?

    I'm 6'1" and 225 lbs. It works great for me, although, if I got really picky, I'd go with bigger springs that were designed for my weight, so I could set the sag properly. That's coming down the road...
  24. Red_250X

    mixing race gas 50/50, need rejeted???

    Yes, there will be slight jetting changes between the two types of gas. You can get away with using the same jetting for both, but it won't be optimal. I run 93 pump gas. I don't bother with the expensive racing gas. It won't make but just a very small difference in performance...there's so many things you can do that will really increase performance. Racing gas will also run hotter and shorten engine life a little.
  25. Red_250X

    Tall seat foam for X?

    Factory Effex has it for the X.