Engine life !

[slickerthanyou]

I agree with the modern 4 stroke motocross engine that OConnor is talking about. I have a friend that has a yz250F (completely stock) and rides it every day in the summer but does nothing for maintenance other than change the oil. well needless to say he has broken 5 valves in 2 years because of poor maintenance. and just as proof a kid he rides with has a yz426f and maintains his very well including valves and hasnt had a thing go wrong with it. some people just dont care.

Yes, maintenance is a factor! I've had a 2008 250 SEII raptor since new, it's piped, air box lid has holes and jetted correctly. I adjust the valves on a regular basis- takes longer to find the wrench than it does to actually make the adjustments. The oil and filter are changed twice a year, and air filter after every ride, new plug every year- we don't ride a whole lot maybe 80-100 hours a year. Going on the fifth year and she runs great! I only run 93 gas in it.

We do not race, only trail runs! I have one complaint on the rappy 250 4-poke, needs one more gear! Rest is awesome!

Awk rides 10 times more than I do and much harder than most- if he is getting-close to 300 hrs, the rest of us should be able to get that also! All about maintenance and a little luck!

 

[OConnor Racing]

http://www.eric-gorr.com/pdfs/4 stroke.pdf

Some Kool-aid from Eric Gorr.

 

[slickerthanyou]

http://www.eric-gorr.com/pdfs/4 stroke.pdf

some kool-aid from eric gorr.

oh-yeah , i like cherry flavor!

 

[joeak47]

I agree with the modern 4 stroke motocross engine that OConnor is talking about. I have a friend that has a yz250F (completely stock) and rides it every day in the summer but does nothing for maintenance other than change the oil. well needless to say he has broken 5 valves in 2 years because of poor maintenance. and just as proof a kid he rides with has a yz426f and maintains his very well including valves and hasnt had a thing go wrong with it. some people just dont care.

Holy crap! No thanks on the four strokes then. 5 valves in 2 years? I guess maintenance is without question the key.

 

[JonS]

Yes, maintenance is a factor! I've had a 2008 250 SEII raptor since new, it's piped, air box lid has holes and jetted correctly. I adjust the valves on a regular basis- takes longer to find the wrench than it does to actually make the adjustments. The oil and filter are changed twice a year, and air filter after every ride, new plug every year- we don't ride a whole lot maybe 80-100 hours a year. Going on the fifth year and she runs great! I only run 93 gas in it.

We do not race, only trail runs! I have one complaint on the rappy 250 4-poke, needs one more gear! Rest is awesome!

Awk rides 10 times more than I do and much harder than most- if he is getting-close to 300 hrs, the rest of us should be able to get that also! All about maintenance and a little luck!

Slick, I don't really think the Rappy 250 classifies as a modern 4stroke. It's basically the same OHC 2v design that they've always used in Yamaha's. Still got 2 big valves and aircooled. Pretty much bomb proof from the factory. IMHO

The high strung 250's and 450's etc is what Ken is talking about i believe. Those are the finicky engines that require the most maintenance, although anyone would be crazy not to maintain their bike no matter the engine.

 

[89blaster89]

you forgot the 5-10 years option, mine was rebuilt in 06 the CORRECT way and its still at 150 psi. WISECO FTW!!!

 

[little3mil]

WISECO FTW!!!

you said it brother!

my old topend was going on over 3 years with the motor that I put together in my garage by myself. simple as this: get a good bore and hone job from any machine shop, use a new wiseco piston, and break it in half decent and your set for a real good while (if its jetted right w/ no airleaks) you dont need some fancy dancy motor work that cost hundreds upon thousands. $50 for a bore $100 for a new wiseco and $25 for a gasket set boom 3 years I:I

 

[OConnor Racing]

Here's the two stroke flavor from Eric Gorr. Go down a few pages to find it.

http://www.eric-gorr.com/pdfs/2 stroke top end and performance.pdf

 

[2smoker85]

i know i dont ride my bikes like a biotch and the last motor i had was 2 yrs old and still strong as the day i built it. as far as i know the new owner is still riding it, so 3 yrs on a blaster motor and probably well over 300 hrs on a +3 240 and no problems isnt bad at all. but the +4 longrod is a little more work in maintenance but much more fun

 

[sporty982000]

I don’t know anyone that rides slow for 5 hours a day. I do know a bunch of guys that beat the living crap out of their bikes for 20 minutes + 2 laps a few times every week. The four stroke maintenance I’m referring to applies to modern motocross engines with sintered metal seats and titanium valves. Bikes like the XR and TTR will be much more reliable. The factories admit that the stock valve springs have a life expectancy of 60 hours. Aftermarket springs and stainless steel valves will last longer but slow you down. When the springs get weak, you get valve float and bounce. This will distort and cup the seating area of the valve and eventually bend the valve. Keep cycling that valve and its head will break off causing catastrophic damage, turning a $1000 rebuild into a useless pile of junk. The key is to never let the parts get to the point of failure. The good news is we’re riding Blasters, not modern motocross bikes.

Thank you Ken for clarifiying that. I was beginning to think my old 4 strokes were in serious need of maintence. lol.


As to a few others:

I didnt add in the poll for longer hours, I thought the last one its been a few years would be enough.

As I mentioned, in part some were posting, they were redoing the top end every 20-30 hours. But I have yet to see them post and select that option.

We can just all be glad and thankfull, that there is many of years ahead for these nice machines.


Sporty

 

[Russell45]

My new to me 88 is untouched and still shows 122 compression. PO cared for it well but it clearly had a lot of use- A arm bushings shot lots of frame paint wear and newer tires. My 06 less used shows 132 on original top end. Will do new piston and hone or bore this winter on the 88 and likely a pipe; port and polish and other goodies.