2-Stroke Maintenence

[fred_durst]

Hey All

I am hoping to get a CR500 sometime in the near future and need some tips on maintenence. I am coming off an XR400, so I have been somewhat on the 'lazy' side of having to do maintence, and have heard that 2-strokes can be a big job, with rebuilds and such. What are the things I need to do to keep the bike running top notch, when to do a top end rebuild, and whatever you need to do with a 2-stroke. Maybe a link to a website I can read ? Thanks again!!

 

[HomeMadeSin]

2 strokes do, generally, require more attention.  Also, generally speaking, the smaller the 2 stroke, the more the attention (or frequency of rebuilds, etc).  The 85's and 125's are run pretty wide open much of the time, so they require top end work sooner.  They should be called GTO's (Gas..er premix, Tires and Oil).

Your XR is gas and go.  The CR/YZ/RM/KX you have to watch the premix (keep it fresh), drain the carb if it sets for long periods, clean or change plugs every few rides, and keep the filter clean.

I would suggest Eric Gorr's excellent book "Motocross & Off-Road Performance Handbook" even if you don't go the 2 stroke route.  It pretty much outlines everything.  It states a tear down as follows:

80cc 5 hours/125cc 10 hours/250cc 20 hours/500cc 40 hours

PS. I don't have the service manual for th CR5 yet, but my old '84 CR250 stated you should replace the piston after every 7 hours of racing.  That's real extreme for general riding, but maybe not for those who want/need to have the best. 

 

[fred_durst]

Thanks HomeMadeSin, I notice you have a 1996 CR500. What kind of regualr maintence do you perform on your bike? Is there a starting procedure for the bike or is it just kick and go. I know my XR I have a starting procudure. Thanks.

 

[HomeMadeSin]

FD:

I added some more info to my last post after yours, so take another look.

I change the oil every 2nd or 3rd ride (I ride about 1-2 hours max. per ride).  I've only ridden the bike 6 or 7 times since I bought it in Jan '02, so I haven't do to much to it.  I'm putting a new spark plug, rear tire and chain/sprockets next week and fully expect to the rest of the season until tearing it down (unless I get really lucky and ride more than I have been).

 

[kev_rm]

clean or change plugs every couple rides? I'd recommend just getting the jetting right and keeping the top end fresh.

 

[Papakeith]

It's a 500, they don't need the attention that a smaller bore 2 stroke needs.
That is not to say that they can just be ignored, but it isn't as big of a chore as some would have you believe.
I just inspect mine on a fairly regular basis. It's a 98, and still has the factory piston in it. Unlike a 2 stroke 80 that may need 1 or more top ends a year with regular riding.
I've had the same plug in my bike since I bought it last year. Still starts on two kicks.
Bottom line. Keep it greased, keep fresh fuel mix in it, check the piston and bore every couple of months, ride it and enjoy.

What kind of riding do you plan on doing? If you plan on being in the woods at all, get a spark arrestor silencer. I would lean toward Pro Circuit. But that's just a personal preference.

 

[Rcannon]

The 2 strokes do require more, but in my opinion they make up for it in being so darned easy to work on.

I changed the entire top end on my yz 250 in a few hours and 150.00 including everything. This included time spent on the computer asking the guys here for help! I was shocked!

I also think the guys that race have to do more. The bikes are so well designed that the work is not too bad. Normal things like airfilters, chains, etc are going to wear out on any bike. The airfilter on the YZ is much easier to dealwith than my old DR 350. The removeable subframe is also great for any carb cleaning that might be needed.

Get a good manual and you will be fine.

The bikes are built very strong. At the speed I ride, the suspension should last several lifetimes.

(as a ps.....I was passed while riding on Saturday. Passed a lot! The last pass was by a KX 60, driven by a girl. I did thump the little boy on the TTR 90. He will have nightmares about my speed)

 

[gwcrim]

Is there a starting procedure for the bike or is it just kick and go.

Once you tune the jetting in, it ought to be easy to start. After a bit of tinkering, my 500 starts on 1-2 kicks. Prior to the tuning, it was a nightmare. I sit behind a desk all day long so my 41 yr old legs don't kick like they used to!

The last pass was by a KX 60, driven by a girl.

See there's this throttle thingy where your right hand grabs the handle bars........ ;)