Which is more work? 2 or 4?

[Dr_Doom]

So, Which requires more maintenance? The 2-stroke or the 4-stroke?

And if there's a thread already what i wasnt able to find, direct me to it?

 

[matt-itude]

I personaly think its about the same over time in dollars. you do the top end on a 2 much more often but it is easier and cheeper to have done or do yourself (no valves timming chain camshafts or valve lash adjustments) and when you change the oil on a 4 there is usually a filter or screen to deal with. in all fairness though you dont have to mix fuel all the time and even though that only takes a second it adds up in time and especially cost. oil change intervals in my experience are about the same between the two used under the same circumstances. My vote is pick what suits you and your riding needs and stay on the TLC and both can treat you good.

 

[darringer]

I disagree. I think overall the 4 stroke will cost more. Also, the 2 stroke is extremely simple to work on. Parts for the top end on the 2 stroke are cheap. And if your talking 250 or larger, then top ends aren't as frequently needed as you think. For example, I did my top end 1-1/2 years ago and on inspection recently, it was still in spec. with 210psi compression. I do 60/40 trail to track time. I also clean the filter after every ride, and keep up on everything else. Personally, I think it's best to pick the bike that you think is best for you. Regardless of 2 or 4 stroke, either bike will take a decent amount of cash to keep in good working order.

 

[Dr_Doom]

Ah. I was going with a four-stroke for a couple different reasons, but i wanted to know what to expect. Hopefully, getting a CRF250 sometime in January if all goes to plan.

And is there much a difference in breaking in a 4-stroke than a 2-stroke? I know everyone has a variety of different routines when breaking in a 2-stroke, is it pretty much the same with 4?

 

[matt-itude]

quite simmilar because the main thing to break in on both 2 and 4 is really the piston and rings.many say to vary (especialy on 4s) the RPM to help assure all moving parts stay oiled because different parts(cams,followers,chains,crank,etc) oil different at different RPMs. basically the oil flings on different parts and different directions at different speeds. the other general saying is dont rev it up and keep it there until its broke in. thats playing it safe. I have friends that say ride it how your gona from the first kick too. I personally play it safe. remember the oil on a 4 stroke is for the engine and trans keep it clean and magnetic drain plugs are cheep ins.

 

[biglou]

The CRF's are running separate engine and tranny oils, btw. The manual gives a brief break-in procedure. Basically, start it for 90-120 seconds a couple times, letting it cool completely in between heat cycles. Then, ride it easy for 30-60 minutes, varying the RPM's, not hammering on it. Stop, change the oil and filter(s), then let her rip. That's what I've done with my YZF's, anyway, and I've had great reliability. I also change my oil (probably) way more often than I need to. Every 1-1.5 tanks of gas, with filter change every three oil changes. The 450 doesn't generate nearly as many metal shavings as caught by the filter as the 426 did for some reason. Either way, both bikes have been rock solid. (knock wood...)

 

[YZ165]

Good info Lou, my 450 dosen't seem to create as many shavings as the old 426 either,.....interesting.

 

[matt-itude]

do the yzfs have seperate tranny and engine oil like the crfs. I wasnt aware of that but i had always thought it was a good idea.

 

[matt-itude]

also are those the only two mainstream model lines of four strokes that are that way? Im used to the standard old fourstrokes. sounds as if the standards are raised.

 

[YZ165]

YZF's use the same oil in the tranny and engine. CRF's have two seperate oils for each. I think the CRF two oil system would be better, but have never had any problems with the YZF setup.

In the 4-stroke world, there are CRF250 and 450, YZF250 and 450, KXF250, and RMZ250. The KX and RM are the same bike with different color plastic. However, when Suzuki and Kawasaki release thier 450's they will supposedly be totaly different bikes. Hopefully sometime in '05.

Of course KTM makes four strokes too. 450 and 525 I think. With the 250 slated for '05.