+2019 GPX FSE250E Air Cooled Modern MX Mountain Goat

Discussion in 'Thumpers' started by Navin, Feb 5, 2019.

  1. ChiefOshkosh

    ChiefOshkosh Been here awhile

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    That was helpful - thanks!
  2. Navin

    Navin Long timer

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    The CST 110 is tiny compared to the same size Michelin I have next to it. I think its a good size for the available power in real off road stuff. Its a good 3/4” shorter sidewall so maybe not the best choice if you want more tire crush at low PSI. I picked the original FSE250E CST over the Michelin last week for my TSE. Down here in soft terrain they are pretty darned good! Running 10 psi but very few threats of pinch flats in Fla.

    To add to the confusion, Im running a 5.10 -18” on my FSE250E and it is HUGE but fits great. I chose it for the tread more than anything else.
  3. ChiefOshkosh

    ChiefOshkosh Been here awhile

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    We have a mix of dirt, rocks, roots and mud in WI. I was out Sunday and ran into some sloppy mud. I was slipping all over so I thought it was time to replace the OEM...heck it's been a good year and the original tire wasn't bad new but after a couple 100 miles on pavement it wore down to the point of...why not replace it. I know there's mixed opinions but, picked up a Kenda Trackmaster II.
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  4. Navin

    Navin Long timer

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    13/42 to 13/38

    Verdict delivered. I have a range of 23-50 MPH ***cruising speed*** in fourth gear. Typical 90 degree turns around local streets are good in second gear, 60 MPH is wonderfully loafy and first gear will pull my trail use on these tires just fine.

    Axle is near full rearward so I will yank a couple links out at some point.

    If it stops raining I can leave the barbershop and get a better pic of the sprocket. Two of the sprox nuts rounded off which is about right. Lock tite plus the included GPX factory open end wrench and Ive had them on and off enough to not complain. Im surprised they didn't all round off they were so hard to unlock.

    7C210195-FD27-460F-B157-1465C6B48123.png
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  5. Navin

    Navin Long timer

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    Cant get much smaller than this!

    F94B274D-18A3-4DD5-B899-D76CF82965D8.jpeg
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  6. Bama67

    Bama67 Cooler in real life

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    So this motor is a true 250cc, whereas the Pitster XTR250 is actually a 230cc.

    So does that mean this one only has 1 or 2 hp more than the XTR or is this one in a higher state of tune?
    Still no big bores available for the 250?
    What engine is this a clone of?

    Sorry for all the questions, I would like a few more ponies but not positive I want to go back to another high HP 250F bike.
  7. Navin

    Navin Long timer

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    My understanding is it’s a fresh sheet, optimized ” Hondaesque “design, shorter stroke, bigger bore, but its not high strung. Like every Zong I’ve tried, its overbuilt, easy to manage with a long flat torque delivery.

    A true 250f with a 4v head it is not. Think more along the lines of a perfected XR200 2V engine.
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  8. Navin

    Navin Long timer

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    Keep an eye on the exhaust header manifold bolts and mid pipe to muffler clamp hardware. Everything is still settling in and took a 1/4-1/2 turn to snug after a nice street ride loop yesterday.

    I finally had her in some northeastern mountains and zero complaints on hills. No need to downshift to fourth up good sized climbs. Loves 55/60 MPH two lanes and she pulls just fine with a smooth, soft, very damped engine purr. No hard or harsh vibes, very refined. These guys build sweet little engines.

    Carb has been a dandy too. In street/DS use Id not even know it’s there. Likes choke for a cold start even in summer temps but no glitches, no stutters, no bogs. I haven’t even opened it to look at jetting. It just goes good out of the box.

    AC69E617-B9D1-4F85-A184-DBAC80BEBF76.jpeg
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  9. Cascade Adventurer

    Cascade Adventurer All the gear, no skill

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    For the single track riding I’m doing here in Washington state I have gone the other direction with a 51T sprocket and I’m happy with it. I spend most of the time in second gear, up to third when trails straighten up. This makes first gear super low. On a typical trail ride I end up using 1st a few times to tractor up steep sections where I’ve stalled. (Not the bike stalling - me) I could see where this gearing would be too low for a more advanced and faster rider on the same trails. For now it's working for me. For dual sport riding trips I will re-install either the 46T or 48T sprocket.
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  10. Navin

    Navin Long timer

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    Like the Shinko tires I installed, my use for the Retro FSE250E is 90/10 street to dirt roads. It will see very few real trails like this and I’m going to swap on fully knobbies and go back to near stock gearing for any more serious (and infrequent) hard off road jaunts. I like a granny first in dirt but I didn’t do any testing in that direction with this bike yet. As a non competitive trail plonker I’ve no doubt it is fully capable.
  11. Cascade Adventurer

    Cascade Adventurer All the gear, no skill

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    0F60961B-9B11-4DA8-B5A7-9E3924E8A1A8.jpeg 20CAA117-83FF-487D-A8A6-C298654BA0E0.jpeg 250E makes a good pack mule. Overnight at Cooney Lake at 7300 feet elevation. Took the Martin Creek trail from Crater Creek trailhead. Rode out on Foggy Dew trail the following morning.
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  12. webmonstro

    webmonstro A Aventura Continua....

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    Seams to be the air cooled version of the nc250 engine that's made by zongsheng ?
    And used in the rx3 AJP etc

    True 250 cc and 6 speed but retains alot of the old honda like engineering including the washable oil filter .
  13. Navin

    Navin Long timer

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    I wish it was a 6 speed but it’s got 5. Workable but so close to excellent. Besides that spot on. It’s smooth too. I suspect fuel injection isn’t far off, carb is a peach though. I’m not shy about jetting my TSE. I’ve nit gone into this carb at all.
  14. savetosave

    savetosave Adventurer

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    Just a heads up to all of you FSE250e owners out there about adjusting your valves.

    I always thought my GPX was an exceptionally quiet motor from day one. When riding the other day, it felt a little down on power, and starting was not quite as crisply as it had been in the past. Putting two and two together, I thought I would check my valve lash just to see where it was at. To my surprise, the intake was down to zero clearance, and the exhaust was at .002”. This was at 28 hours, and 867 miles on the bike.

    Of course, I couldn’t find a “real” factory spec, but years of XR Honda wrenching lead me to setting both intake and exhaust to .004” clearance, and she is ticking away nicely now. As they say, “Slappy Valves are Happy Valves”

    I don’t think there is a long term wear issue here, I just think my bike was not right from the get go. I’ll check it again in 30 hours, and give some feedback. BTW, I picked up a nice boost in off idle torque with the valves set right. Sweet!

    OTOH, my neighbor across the street just picked up a new 2019.5 FSE250E, and his valves were ticking away nicely upon firing up, so YMMV.
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  15. Traveller128

    Traveller128 Long timer

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    They move a little after a few hours. They tighten up as they seat. Since the clearance isn't a lot to begin with, you end up with what you experienced. Most air cooled motors do this during break-in, which is why the factories all recommend around a 5 hour initial adjustment. Keep an eye on it, but it usually doesn't move much after the initial adjustment. Done that with all our Honda, Kawasaki and Yamaha air cooled motors over the years.
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  16. GlennR

    GlennR Chasin' my tail

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    Any news about the GPX 450? Thought we'd hear something about it soon.

    (I can't seem to find the thread about it.)
  17. OUTERLIMITS

    OUTERLIMITS Been here awhile

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    I kind of like it without the shrouds. Did you just take them off or was there some damage?
  18. Cascade Adventurer

    Cascade Adventurer All the gear, no skill

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    I removed the shrouds to reduce weight and to eliminate something that can break. (Weight is important to me - not so good at lifting heavy things.)
  19. bark sampler

    bark sampler Been here awhile Supporter

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    I’ve been looking through the FSE250E and FSE250R threads trying to determine what the differences are on the chassis side. Is it the same with exception of the forks? Specs look the same, but that doesn’t mean much.

    Is the E a lower spec suspension front and rear to keep the price down? Anyone looked them over side by side?
  20. Navin

    Navin Long timer

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    The earliest R bikes had Fast Ace suspensions. The later GPX will all have identical SCZ parts which are more mainstream and easier to service. They are on my E and seem to match the Fast Ace stuff as far as quality, which is good.
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