Street usage gives busted engine?

Hi everyone!

Rather new to the dirtbike and dual sport world, and have searched the forum over and over again..

Learned alot, thank you all.. :)

Probably missed it, but anyhow, here´s what I´m wondering:

I have a street legal WR426 -01, which I mainly use for heavy Enduro, love the trails and really like it in the woods, but since I read a post regarding Crankshaft Bearing jammed

I feel a little worried..

Is this something that happend to this one rider alone?

I use the bike for transportation to and from the trail or wherever I rode it, so it can be up to 35 km of pure road riding..

Am i to be afraid that it wont hold? I mean, It´s a foursmoke, should it really be that sensetive that it will not tolerate streetriding without breaking? Sounds a bit strange to me.. :D

Sure, there is little oil compared to a streetbike, but its changed frequently (every 5-10 h. riding) and tireware is ABNORMOUS when riding road, but the rest of the engine or bike for that matter shouldn´t brake due to streetriding..? Or am I wrong? Should I buy a car to transport it to and from practise? (will probably do so anyhow, due to cold winterdriving on the road is not appealing to me..)

Thanks for your inputs..


You shouldn't have any problems riding it on the road unless you shift without the clutch a lot. It is very hard on the gears. Everything else is the same except there is no wheel slip so it puts a lot of load on your tranny. Just be careful and shift easy :)

The guy who had the problems you referenced went thousand miles or so on the street at highway speeds and no oil changes during a multi day trip. These bikes are not dsesigned for that type of dual purpose riding. :)


So I shouldn´t be worried then.. :) Clutch is ALWAYS used in roaddriving, and mostly in the woods aswell, since I´ve ridden a streetbike for the last 5 years it just seems as the right thing to do.. :D

Also, I´m aware of the "whatever you called it" in the transmission (drivechane and sprockets) Keeping an eye on them constantly..

The bike´s up to about 120 hours of riding in total, and I hope to get much out of it yet! Lots of people I´ve been talking to though, say that they aren´t built for street use at all, and I will have problems in the future.. But in my opinion, that WAS true in regards of the 2-smokers.. In a thumper none of these problems should occure.. Although I´ve been thinking ´bout making the oil container larger by buying an oilcooler, and mount it.. Should give approx 2-3 dl. more oil in rotation and better cooled oil when going on the road.. Not to mention that there should not be a problem in extending the oilchanges to up to 15-20 hrs riding then.. Could there be a problem for the oilpump to manage this? :D

Unless you're going across the country... don't worry about it. Bikes are tough and easy to repair... Have fun on and off road and don't worry about the bike.

Dont worry about it. I have a set of motard wheels and regularly change over from the nobbies so I can go and show the posers on their 140 hp sports bikes how to carve a twisty piece of bitumen up, good and proper! My girlfriend also rides a suzuki sv650 road bike and I go on day rides and bike rallies with her occasionally. The old girl sure gets a good revving but It hasn't worried it yet.

I doubt increasing the oil volume will make much difference. After a good long ride I can pull out my dipstick and wipe the oil off it with my hands and its always only warm,never hot! Try that on an xr or dr and you will burn your fingers.

Just go easy on your gear changes on the road and I doubt you will have any problems. I have almost 10 000 kilometres of combined dirt and bush use and my valves havent even needed re-shimming yet. Keep your oil changes regular and your airfilter clean and enjoy :)


Caps lock button stuck? :)

:D I think he is trying to get his point through to not ride your bike on the road or something :)

So.. Question still remains then...

In some cases it seems as it brakes in other not.. :)

More inputs?

The connection rod bearing got jammed on my motarded wr426f 2001 out riding on the highway, after approx. 5000km, Oil and filter is changed every 500-600 km on my bike. Don't know exactly what caused it.. Had my engine rebuildt, and the guy who helped med told me not to push the revs to much. I might have been pushing it a bit to much... anyway it's back on the street, and i hope it will last more than 5000km this time. :)

The connection rod bearing got jammed on my motarded wr426f 2001 out riding on the highway,...

Don't know exactly what caused it..

Well then, any connection/relationship between how you ride, your maintenance intervals, and your engine failure is completely speculative.

First order of business is determining exactly why the failure occurred, I know I would be just a litlle curious to find out what happened to CAUSE the failure before I started throwing new parts in the engine.

Would a high quiality synthetic oil alleviate these problems?

Mine has been doing fine. but i dont have that many miles on it (maybe 2000). the rear sprocket doesn't have a "cush drive" like a street bike, and thats the main concern for damage to the tranny. as for the oil coller for extra oil storage, sounds like a good idea. just make shure its not in a place that it can get punctured when riding in the woods.

My bike rode 2000 Kilometers of road this year: we were two on the bike for half of it. No problems at all. Oil changed at every 1000 KMeters. Total 4000 Km of road in its life.

I logged 7900 Kms, paved and gravel roads, and various off-road terrains...still running flawlessly. Amsoil synthetic every 1000 Kms. (after a good 650 Kms break-in) Higher 15/50 gearing lowers RPMs and creates a better 'under load' engine operating condition. Also, a tight drive chain can cause excessive stress on tranny and engine. Keep it on the slack side for street usage. (1.75-2.00 inches)

Higher 15/50 gearing lowers RPMs and creates a better 'under load' engine operating condition

Yes. My gearing is 16/44 for the road. The engine purrs at 60 miles per hour :)

:jawdrop:Holy cow, Math! Your gearing sure is nice and high...You're good for 121 MPH in 5th at the 10500 RPM rev-limiter; At 60 MPH, you're turning only 5200 RPMs. Any problems launching and for lugging in the tight technical stuff??

I don't like engines to rev high constantly (like on the highway for example).I don't know if this feeling makes sense but anyway.

I have two wheel sets so the street rear wheel is mounted with that 44 t and the offroad rear wheel wears a 48. This way I automatically get a lower gearing when going offroad. 16/48 is still too fast for woods riding though. When I go for long rides on open trails, I keep the 16t on the front and just put the offroad wheel giving 16/48. But if the day is planned to be tough and technical, I take an additional minute to install the front 14t giving a 14/48 ratio which is just nice for woods riding. I rarely do it since my partners here like to ride open trails.

Can a 16 tooth fit on a WR450? I think it wont clear the engine case? I think we are restricted to 15 tooth on our models. :)

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