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Real-world piston life expectancy?

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These question is for anyone with direct experience with these bikes.

The manual says piston replacement at 15 hours:

1 - Have you actually had to replace a piston @ 15 hours?

2 - If not, how many hours before you did replace your piston?

3 - If you're still running the stock piston, how many hours approximately do you have on it?

4 - What kind of riding do you do?

Thanks,

-Bob

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15 hours is ridiculous. Unless you're a pro running WFO all the time in dusty races and constantly overheating your bike you can forget about the 15 hour schedule. I have 63 hours on my X and I just now changed the piston. I clean the filter every 5 hours of run time. Dust has never really been an issue since I usually ride alone. Half of those 63 hours were spent in the desert and the other half in the woods.

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I changed the stock piston at 50 hours and it was ready. I went to a JE high comp and am going for 100 hours on it but I still changed rings at 50 hours and they were due for sure. District 16 senior A enduro rider.

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70+ rings at around half way.. A level offroad rider. A few races and alot of practice and play riding.

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I have a 450x so you may consider it to be different, however for comparative measure purpose it shouldn't much matter.

I have about 600 miles on my bike now and it's running fine, no blow-by, and burns nearly an unmeasurable amount of oil. I also did a pole (we we had the ability to do so) on piston replacement in the 450R forum, do a search to see the replies, I think you'll find it useful.

I will do a piston replacement this winter. I estimate having well over 1000 miles by than.

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I still have not replaced my piston, thinking about it though...Have not really noticed anything bad about the performance.

Cant decide whether or not to get a high comp piston or get another stocker. (i just dont want to run race gas just to go out play ridding).

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We changed ours at 100 actual meter hours. Piston and rings still appear to be in really good condition. We don't do any organized racing and we ride at 5,300 ft elevation in the desert SW. We only put out about 80% of sea level HP at this altitude, so things may just last longer.

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I still have not replaced my piston, thinking about it though...Have not really noticed anything bad about the performance.

Cant decide whether or not to get a high comp piston or get another stocker. (i just dont want to run race gas just to go out play ridding).

You won't need to run race gas. Mine runs perfect on pump gas with the JE 13.5 to 1 and it does make a noticeable difference in power.

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40oz,

I agree with Danceswithtrees, no problem with pump fuel with JE 13.5. I only run 93 octane.

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Man, I tell you what....

you guys are evil, always talking me into buyin' stuff for my bike...cant you people let me go a month without buying something to pimp my bike out.. :applause:

Thanks a lot guys for the info, this site rocks due to people like you!!

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My 05 X just blew up, no warning. Just hit the E-start and bam!!!! I am guessing about 300-400 miles on it. Just easy riding no major mods to the bike. I know one thing for sure, when I get this thing back together it will instantly appear on Craigs list. First decent offer gets the prize....I have always been a Honda fan, but this particular model has left a very bitter taste in my mouth. As far as the bang for your buck goes, this thing isn't worth much I would guess 5 cents worth of performance 20 cents worth of reliability and about 75 cents worth of repairs....Sorry!!!!

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You know, I'm pretty surprised at the fragile motors these bikes have. Replace the valves, piston, and rings within 50 hours? Most of our friends have KTM's, and they are amazed that the CRF250's are so short lived. Guys here seem to think nothing of rebuilding the engine at 15-50 hours. I think that's really poor engineering. Especially for an off road, not race bike.

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That's why I ride a Yammy! my 2002 250F has never had any problems. Had to adjust 1 intake valve that that was the end of that. Aside from that, the only other issue was a seized front wheel bearing. Dont mean to rain on your parade, my buddy's got an 03 CRF and its never given him any problems either...Maybe just the luck of the draw?

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My 05 X just blew up, no warning. Just hit the E-start and bam!!!! I am guessing about 300-400 miles on it. Just easy riding no major mods to the bike. I know one thing for sure, when I get this thing back together it will instantly appear on Craigs list. First decent offer gets the prize....I have always been a Honda fan, but this particular model has left a very bitter taste in my mouth. As far as the bang for your buck goes, this thing isn't worth much I would guess 5 cents worth of performance 20 cents worth of reliability and about 75 cents worth of repairs....Sorry!!!!

I'm confused :applause: about what you mean by just blew up. Did alqueda wire a bomb to your electric starter? :prof:

Seriously, thats awful- but what failed in the engine? :D

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You know, I'm pretty surprised at the fragile motors these bikes have. Replace the valves, piston, and rings within 50 hours? Most of our friends have KTM's, and they are amazed that the CRF250's are so short lived. Guys here seem to think nothing of rebuilding the engine at 15-50 hours. I think that's really poor engineering. Especially for an off road, not race bike.

I hate to say this as I have had more fun on my X than any other bike I've had but I'm starting to feel the same way. In 2 years I've had my motor apart 3 times, 2 pistons, 1 new head and valves and I'll need new piston and rings by midsummer. I'm hoping it'll hold together until end of summer without anything disastrous happening. By then maybe my new 07 KTM 250 xcw-f will be here. The ktm sxf's are going over 200 hours without opening the motors, at least that's what I keep reading and hearing.

I'm not going to start Honda bashing, but I would like to see the X motor built for more longevity as I think those that choose the X are mostly trailriders and want a reliable bike.

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I hate to say this as I have had more fun on my X than any other bike I've had but I'm starting to feel the same way. In 2 years I've had my motor apart 3 times, 2 pistons, 1 new head and valves and I'll need new piston and rings by midsummer. I'm hoping it'll hold together until end of summer without anything disastrous happening. By then maybe my new 07 KTM 250 xcw-f will be here. The ktm sxf's are going over 200 hours without opening the motors, at least that's what I keep reading and hearing.

I'm not going to start Honda bashing, but I would like to see the X motor built for more longevity as I think those that choose the X are mostly trailriders and want a reliable bike.

The 250SXF is holding up well. A few bombs out there but not bad. I think the SXF if ridden hard it does get loose. I also hear the meat of the KTM power is almost 1500 rpm less plus better parts at the OEM level.

Not to bash the CRF either, The aftermarket hop-ups have made it a sweet machine to bad Honda did not go that extra step. I have seen 450RFS shake apart when ridden like a 2 stroke.

Time will tell..

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To be totally honest, I have no idea at this point as to what happened to my motor. I have not gone deep into the motor yet. I was on a simple trail ride and taking it easy, as I have been having fork seal issues. I had gone about 7 miles when I noticed my throttle was hanging open momentarily. I pulled over and turned off the bike to see if I could find something wrong with the cables. I then got back on the bike and hit the E-start. when she fired up, all hell broke loose. as I explained in another post, it sounded as though someone was inside my motor with a hammer trying to bust his way out. It fired up a second time with the same results. After the two starts she refused to start. Initial inspection revealed nothing. Valves appear to be within specs, but I feel the problem is deeper inside. I can't turn the motor over by hand even with the spark plug removed. There was absolutely no warning up until the time the noise was heard. She was running fine except for the throttle issue.

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Do any of you have some measuremnts of the Cylinder, Piston, Piston to Cylinder clearance and Ring end gap new and after the 50-70 hours?

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