Crf-r to crf-x trans swap?
  • terrible
    Posts: 8
    Joined: Wed Mar 18, 2015 6:37 am

    Crf-r to crf-x trans swap?

    by terrible » Sun Mar 29, 2015 5:53 pm

    Looking for a lower first gear for my crf250R. Can I swap the main shaft and 2nd gear from an X and get the rest of the trans to still jive?

    Since second gear is the same on both trans would it be possible? Thanks!

    Would it be any better to just gear down on the sprockets?
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    JimDirt
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    Joined: Sat Nov 25, 2006 6:31 pm

    by JimDirt » Sun Mar 29, 2015 7:10 pm

    If the 250X/R is the same as the 450X/R , then they will not fit , all the gears , as are the engine cases , are wider on the X , so nothing will interchange as far as i know

    I know they make a ($500) "kit" for the 450R to make it a wide ratio , but i do not know if one is available for the 250R

    I believe you are going to have to either go with a lower gearing/larger rear sprocket , which will lower your overall speed , or get a auto clutch so you can ride thru the places you need lower gearing and be the same elsewhere

    If you ride strictly off-road or single track this is about your only choices (other than trading the R for a X)

    If you ride both track and trail as i do on my 450R , then go with a larger rear sprocket and get a 120 link chain , and a extra master link , so you can use the "stock" gearing for the track , then swap rear sprocket (or another rim with a different size sprocket) , and swap back and forth , and adding the extra links with the swap to the larger sprocket works great , this is what i do on my R , and since there are only a few links added at most , you wont notice anything in the wear of the chain/sprockets when adding the extra links , i go from a 49 to a 52 and anywhere in between (50 or 51) with just 1 extra link and a extra master link
    2020 CRF450R
    2006 CRF450X
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    Weiser , Idaho
  • terrible
    Posts: 8
    Joined: Wed Mar 18, 2015 6:37 am

    by terrible » Mon Mar 30, 2015 5:43 pm

    Well just looking at parts cataloges its tough to tell gear width. Kind of a bummer, seemed like a good idea.

    I do have a rekluse clutch but I'm not 100% in love with it. It seems to grab a lot and requires a pretty low rpm to disengage. Thought about pulling the cover and seeing if I could pull a few of the balls out to get a higher engagement point.

    Might try a different final drive ratio when it comes time for a chain/sprocket swap.
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    JimDirt
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    by JimDirt » Tue Mar 31, 2015 8:52 am

    I hear ya , i have ridden bikes with the Rekluse and honestly , i can do just as well using the stock hand operated clutch , i never liked the way they work/feel , i will say that gearing helps , i would also PM Ken and ask him if anyone has tried , or measured to see if the "450R Kit" will work with the 250R , i am guessing it will not since it does not say it does , but it does not hurt to ask

    What i am referring to is this , maybe one will fit , i don't know , you could ask Ken

    http://www.crfsonly.com/catalog/product ... ts_id/3699

    http://www.crfsonly.com/catalog/product ... ts_id/4580
    2020 CRF450R
    2006 CRF450X
    Image
    Weiser , Idaho
  • terrible
    Posts: 8
    Joined: Wed Mar 18, 2015 6:37 am

    by terrible » Tue Mar 31, 2015 9:00 am

    I notice with both of those kits the 1st gear ratio is retained? With the 250 X/R trans the first gear is a tooth lower in the X trans.
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    crfsonly
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    by crfsonly » Wed Apr 01, 2015 8:39 am

    Unfortunately, none of the R/X transmissions are interchangeable. The reason the wide-ratio transmissions we offer for the 450R are only 2-5 is because the added cost in doing so. As you know, first gear is on the mainshaft. Adding the mainshaft to the kit would double the price. These kits rarely sell at the current price.

    Ken
    OEM Parts for Honda - Yamaha - Suzuki - Kawasaki: http://yeltrik.com
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