HONDA CRF250 RALLY OWNERS

Discussion in 'Thumpers' started by ferdiepick, Mar 18, 2017.

  1. SRTie4k

    SRTie4k Northeast Explorer

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    Did ~70 miles of trail scouting this weekend on a mix of easy and stupid trails.

    Just an FYI if any of you haven't done it yet, the 13-40 drive ratio is what this bike should have come with from the factory. Acceleration is SO much better, and you're in the sweet spot for offroading. And I can still hit 65 easily.

    In the first pic we ended up riding through a pond that was overflowing the trail. There were a few starter beaver dams that we broke up to lower the water a little, but it was still easily up to the tops of our wheels.

    Second, we "accidentally" went down a super gnarly Jeep trail, very steep and with huge boulders all over the place. That was a real test, ended up smacking the skid plate really good trying to get around, but it held up fine.

    [​IMG]

    [​IMG]
    Tritwin, Phmode, okiegtrider and 3 others like this.
  2. LuxADV

    LuxADV n00b

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    Hi everyone,
    thinking about doing the ECU swap from the Japanese CBR as it seems to be the cheapest and easiest power mod. Everyone seems to be quite pleased with the results. From what I've read there is mostly a noticeable torque increase in the lower rev range, which is good ... but I'd really like to have those +3-4 ponys overall. If the CBR engine is indeed mechanically identical, shouldn't the ECU upgrade give us 29 hp and not just a different torque distribution?
  3. Yuri_Ivanovich

    Yuri_Ivanovich Adventurer

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    As far as I know off no one has measurable comparison between the ECU's. No dyno readout with horsepower comparison, no results from using app on your phone to measure acceleration, not even 2 videos showing acceleration before and after. It's all based on "feeling more power". While many have sensitive butt-dynos it is not an accurate way to measure power. If you go for the Japanese CBR ECU swap, please do a before and after measurable comparison of power and share with us (pretty please , both ECU's, video of dash, flat ground, third gear, full throttle from 2000 rpm to redline, repeat in other direction to account for wind). Personally, if I was playing around with the ECU, I would use Power Commander V with Autotune (or Power Vision 3).
    Since no one has dyno horsepower measurement from the CRF with CBR ECU, it might be that the upgrade does give you 29 hp, with it being most noticeable in lower rev range.

    Some say that the cheapest and easiest power mod is new sprockets.
  4. oMMo

    oMMo Adventurer

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    Different exhaust and intake system, which might lead to more grunt down low, but less top hp. And was it only the CBR 300 or the 250 as well that had a different intake camshaft?
  5. Phmode

    Phmode Most of the gear, little idea!

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    Certainly and absolutely no more power with the Japanese ECU fitted.
    Much better pulling power below 6,000.
    Climbs hills easily in most gears (which it certainly never did before).

    Different sprockets do not give you more power.
    New sprockets do not give you better low down acceleration AND the same top speed. It's one or the other, take your pick.

    if you are capable of taking all the measurements you ask for, let's see you do it. I tried and failed miserably and I ain't paying good money for a dyno run to prove it has no more power, just to satisfy the doubters...

    As far as I know, not a single owner who has fitted the Japanese ECU has been anything but delighted and that speaks for itself.

    Like I keep saying, don't knock what you haven't tried. Brian
    Pilomajajo likes this.
  6. Yuri_Ivanovich

    Yuri_Ivanovich Adventurer

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    Hmmm.

    I specifically didn't "knock" anything. I pointed out that no one has been able to share a visible/measurable proof of the difference between the ECU's. And I detailed one cheap and easy method to get real visible/measurable proof of the difference. Once and for all. To silence all critics. I even added "pretty please".
    mylsmkj and randypower like this.
  7. Phmode

    Phmode Most of the gear, little idea!

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    Hitting 65 may work where you live, being limited to 65 where I live would mean being run over by trucks :-)
    northumbrian likes this.
  8. SRTie4k

    SRTie4k Northeast Explorer

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    I specifically stay away from interstates on this bike. That's what my Super Adventure is for.
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  9. Phmode

    Phmode Most of the gear, little idea!

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    Oh, I'm not talking Interstate/Motorway/Autoroute here. Doing a mere 65 on a normal road in the UK will get you squished by a truck which is limited to 55...:-)
  10. EZ-D

    EZ-D Davidprej Supporter

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    Yes and there are 2 lane roads in Texas w/ 75 mph speed limits. I think his point was that he doesn't use his 250 on those roads.
  11. Swamper

    Swamper Been Nowhere Done Nothing

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    Any of you guys tried out the Dunlop Trailmax Missions. Looking to get a set for my Rally but looks like a size up in the rear.
  12. rexbro

    rexbro Been here awhile

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    I’m using them and really like them. Link to pics in Trailmax Mission thread.
    90/90-21 & 120/90-18 sizes - 7160 miles on this set so far
    Front new
    upload_2021-6-30_19-18-14.jpeg

    Front now
    upload_2021-6-30_18-58-28.jpeg

    Rear new
    upload_2021-6-30_19-19-18.jpeg

    Rear now
    upload_2021-6-30_19-0-32.jpeg
    Swamper, randypower and RockyDS like this.
  13. Heavy

    Heavy Been here awhile

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    Well, I drank the coolaid and joined the ranks. Found a 2018 with under 800 kilometres for a sensible price.
    20210624_154657.jpg
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  14. Brokenoldbiker

    Brokenoldbiker Adventurer

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  15. c21

    c21 Adventurer

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    @Brokenoldbiker
    Try Bridgestone AX41 instead....they are quieter then the OEM IRC tyres.
    Brokenoldbiker likes this.
  16. Swamper

    Swamper Been Nowhere Done Nothing

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    I think I'm going to try out the Dunlop Trailmax Missions so I'll use the bike a little more. I've been using the MT21 Pirelli's for mostly off road riding but find I don't use the bike much because I haven't been doing much off-road riding, nobody to ride with and don't want to ride alone in the Sierra trails. Also I got a Rebate coupon from Dunlop from their Rep. at the BMW MOA Rally for $100. So I can get a set for $135, hard to pass up. Only thing was the oversize rear available, diameter equals higher gear. Maybe consider doing the front sprocket change?

  17. rexbro

    rexbro Been here awhile

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    No howl from either tire yet - the rear does feel more knobby like as you lean into it though.
    I’m amazed at over 7k miles on the rear - should make 8-9k miles no problem. Front should make 12-15k miles.

    @Swamper - The rear sits a bit taller - not a problem for me but something to consider.
    I can feel the taller gearing effect but it’s probably not enough to warrant a front sprocket change for casual DS and road use. It makes my speedo and gps readings almost jibe though.

    :ricky
    Brokenoldbiker likes this.
  18. Swamper

    Swamper Been Nowhere Done Nothing

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    I used the 606's in the same sizes and it robbed a little power on the uphill climbs. Never noticed any difference on the street, highway.
  19. RowBust

    RowBust Long timer

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    The 250 Rally is already over geared, if you fit a bigger diameter tyre best to gear it down, you won't lose top speed as you'll actually be able to rev it higher
  20. Swamper

    Swamper Been Nowhere Done Nothing

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    Picked up the Mission tires yesterday, probably mount them up on the 4th, or Monday. I'll see how they work and figure out if I'll be doing the gear change.
    20180914_144756.jpg
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