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General Questions on 2009 RMZ-250

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1/ We bought a 09 a year ago. It's been a great bike so far. Some of those die-hard carburator fans might like to stick with an 09 as it's the last year for a carb.....LOL. So I wonder....if in 5 years from now, it will be more, or less, desireable than the 2010s?

(He's driven a 2010 and says the big difference is instant power, which he likes, but says it would take some getting used to.)

2/ It's my son's as he outgrew the KTM 85 SX he had before. The KTM was a nightmare of maintenance expenses, although I suppose any 2-stroke needs frequent TLC. Any idea how much use (hours or racing seasons or whatever) will the Suzuki 250 will take before a rebuild is required?

(Symptoms will eventually be an indication, but I might do a rebuild over a winter between seasons if I was to suspect trouble might occur 1/2 way through the next season)

3/ Is the cylinder Nikasil plated?

4/ Even though he raced it last year, he still has a probem with warm starts. Starting it cold is easy....choke ON, a few twists of the throttle to activate the accelerator pump, and give it a coule of kicks. Hot starting is fairly easy.....just use the Hot Start Lever. But it's those warm starts....He drives the bike to the starting line getting it only mildly warmed up, or drives it from our shed to the house, and stops it. A few minutes later, it seems to take forever to start in it's slightly warmed up condition. Any tips on techniques?

5/ He's still a benginner enough he doesn't need any more from the engine or chassis at this time, but are there any recommended mods for this bike?

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I'll try to help with some of your questions...

#1 I don't have a clue and don't believe anyone else will either.

#2 Sorry but the small bore 2 strokes need pistons like Carter need liver pills...

The RMZ 250??? Depends on your bike & how he rides. We had to replace the crank with 18 hours. The guy that does our shop work talked to my son and found he was riding it like a 2 stroke. High in the rpm range all the time. Got him out of that but then did a top end at 60 hours and another crank again at 120 hours which we did a piston at the same time too...

#3 YES it is Nikasil plated.......(which is good)

#4 I have found that these bike need jetting adjusted a lot more than 2 strokes. If it a starting problem it needs more or less on the pilot jet.It seems to be more of a wet air v dry air thing.

#5 Mod's- Depends on what he racing?? MX or off road. If it mx, you can port the head but you can do too much porting causing it to need race gas. You can do the P/C stage 2 cams but you need light porting also.

If he's racing off road we did the Athena 290 big bore kit which give us a lot of low end torque so we could then change the gearing up without losing any low end power. Then we did the cams. My son now rides two expert classes. One in a 250 ex and the other in a 13 to 29 year old open class.....

Hope this helps you out...

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Thanks guys. I appreciate the comments.

The starting issue is the same now as it was when new, so I'm thinking the valve adjustment should still be close to where the factory set it.. I have to admit, I never did adjust the idle mixture screw. Also, apparently he has found a technique that works when the engine is only slightly warmed up....he puts on the choke and operates the hot start.

Regarding longevity, I think I have a grasp on it from the history the first replier detailed. Not as good as I hoped, but much better than a 2 stroke. I think it will be fine for this season, but I should check the compression now, and maybe the flywheel for bearing play as well. Then I have something to compare it to at the end of the season. Not sure about the compression check as I think the bike has some sort of pressure relief system that comes into play when kicking it over. I think I can do a leak-down test with some equipment I made for car engines....just need to make a plug-to-air adapter to fit the engine.

I was asking about the Nikasil because it may take some time to have it re-plated as I have to send it away for that. Not something I want to do during mid-season due to the delay in getting it back.

Porting sounds like a good move, although if the cylinder ever suffers major damage, I would probably consider a big bore kit.

Right now, he's got more bike than he can use. He doesn't use it like a 2-stroke at least. His only 2-stroke, the KTM 85 was bought in the Fall. He physically outgrew it over the winter, so we went with the Suzuki 4-stroke and he never got used to driving a 2-stroke. His only other racing experience was 1 season of Harescrambles riding a CRF150.

Here's a video from his first year doing MX...you can tell he's slow, although there's been a huge improvement at the end of last year, but I have no video for that (look for blue helmet, yellow bike):

Some of the video is at a practise track and some of the race footage is pretty bad. He'd had a bad spill during the morning practise. I shouldn't have let him race, but he wouldn't admit to the ringing in his head until the end of the day.

Until he starts demanding more from the bike, it won't need any mods for now.

ps: so far, the bike has been great....the only issue I have with it, is checking or changing the sparkplug requires a fair bit of bike dissassembly.

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I know in the 08bikes if you pull the hot start and choke it at the same time and give it a quick pump of the throttle, it starts 1st kick almost every time.

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