rlcowder

Member
Jan 12, 2006
10
0
I an old guy who just got a nice near new 2000 YZ250. It has the original tires and everything is stock. It looks like what the owner said, unused, he took it away from his 16 year old son after he had a crash and the kid never rode it agin. I got a test ride and it's very powerfull, starts 2nd kick, and just needs a back fender. Now the questions. I have only owned 4 strokes, mostly XRs and don't know anything about 2 strokes. I have been doing a lot of research and still would like to cofirm what I think I need to do.
1st. Starting, I was told this is the drill. Turn on gas, tip bike till gas comes out overflow, choke on, half throttle, get piston to tdc and kick. Once it fires hold it 3/4 open in a high rev to burn off carbon. I think all is ok but the 3/4 open thing, that seems a little destuctive to me.
2. Should I do the top end kit just to be safe or run compression test to help decide.
3. If a 2 stoke is jetted correctly I should have no issues with plug fowling. true or false
4. a factory service manual will give me pictures to help me with my rebuild if that's what I need to do.
5. I was going to use Rotella full synthetic 5w-40 ( non energy conserving) in the gear box, would that be OK? How much does it take? I don't have a manual yet.
6.Best online dealer for parts?
7.Best premix ratio and oil to use? I was just going to use something like castrol tts at 32:1
8. is 94 octane OK, or will it need higher?

I would rather put a couple hundred into it to make sure it OK than risk toasting it and needing more money. Here's the real kicker, I got it for $400!!! :laugh: The owner was going away for 3-5 years (HINT) and needed the cash for some FEES. (HINT)

Let me hear some opinions please. Thanks
 

i_955

Member
Dec 18, 2004
265
0
1st. Starting,
Turn on gas, tip bike till gas comes out overflow = Y
choke on = Y
half throttle = N
get piston to tdc and kick =Y/N, it doesn’t matter (it isn’t a 500 two stroke)
Once it fires hold it 3/4 open in a high rev to burn off carbon = NO

I put mine in 2nd and move it back & forth a couple times to suck a fresh charge of fuel into the cylinder. Once it fires turn the choke off, then pull the choke on, then turn the choke off etc for a minute or so until it starts to warm up nice.

2. Should I do the top end kit just to be safe or run compression test to help decide. = Y/N/Maybe, wouldn't be a bad idea to buy a cylinder to base gasket and take a look.

3. If a 2 stoke is jetted correctly I should have no issues with plug fowling. true or false = T

4. a factory service manual will give me pictures to help me with my rebuild if that's what I need to do. = T

5. I was going to use Rotella full synthetic 5w-40 ( non energy conserving) in the gear box, would that be OK? How much does it take? I don't have a manual yet. = 750ml (it is stamped on the side of the case in BIG BOLD Letters).

6.Best online dealer for parts? Get to know your local Yamaha dealer and http://www.mxsouth.com/ is good.

7.Best premix ratio and oil to use? I was just going to use something like castrol tts at 32:1 = 32:1 is recomended by Yamaha and works fine.

8. is 94 octane OK, or will it need higher? 94 is fine.

Its WAY more bike than your XR, be careful and have fun.
 
Jan 10, 2006
94
0
i_955, Great answers.

BIG NO on 3/4 rev to burn the carbon. Allow the bike to warm up before you start gasing.

That is a lot of bike so be careful and get used to your new baby.
 

rlcowder

Member
Jan 12, 2006
10
0
Thanks alot for the detailed answers. I feel stupid for not knowing the oil measurement was marked on it. I get to pick up the bike tomorrow. I ordered the service manual today. You'll find me in the emergency room tomorrow evening.
 

i_955

Member
Dec 18, 2004
265
0
rlcowder said:
. You'll find me in the emergency room tomorrow evening.

Remember to look where you intend to go and not at the front fender or the dirt a couple inches in front of the fender or you'll be dusting yourself off a lot. :aj:
 

SEM66

Member
Dec 15, 2005
16
0
I was pretty much in the same boat as you and I came away with a cherry '02...i was gonna mention that you might not need to do all those hi-jinx on startup depending on your location/climate...but since I don't know what the weather's like in I don't know, i can't give you any reference. I'm in mid-Texas and I haven't once had to use the choke or any of that tipping, praying, facing north, saluting, etc...'course its been pretty warm down here lately. The manual is a great idea though, even has some good jetting info.....get ready to have a blast though.....freakin' hang on!

oh yeah, I got a new set of plastics from Motosport.com for a great price w/ free shipping and the stuff showed up in 2 days Fedex.
 

jayfrank5074

Member
Sep 25, 2005
10
0
hmm, 2 weeks ago it was 37 degress farenheit, i simply pulled the choke, kicked twice, and bam, running. immediatley took choke off. this is on a 04 yz250. procircuit pipe, shorty silencer, stock jetting(i think i just got the bike, and havent checked it.) when its warmer (55+) i dont use the choke at all, one kick. and if its above 45 with the choke on it also starts in one kick. i have never had to tip a bike. and i NEVER touch the throttle till it cranks. when i have tried giving it some throttle upon cranking in the past(other bikes, when i was younger), accidentally, it usually floods, and possibly fouls the plug.

as far a getting bike to tdc, its not necessary, but mine sure cranks way better when i do it.

oh btw, i must say yes this is alot of bike. cant get enough of the "hit"
 

rlcowder

Member
Jan 12, 2006
10
0
I got the bike cheap so I took it to my mechanic and I'm having him give it closer look. Because I don't know it's history first hand I'm having him put in a top end kit, new chain and sprockets, new Dundlop 773's and some hand guards. I went to a 53 tooth rear sprocket because I only ride tight wood in western PA and I will never need to go above 60mph anyway. Do you guys have any info on how much of a effect on mph in a certain gear that would make? I looked up the ratios and it will be going from 3.42 to 3.74. I figured it would be like my old Trans am and changing rear end gears. I don't think it will cut the speed down too much. Do you think that is a reasonable change for all woods and hills riding?
 

rlcowder

Member
Jan 12, 2006
10
0
Oh and I got some MaximaM 2 stoke oil and 94 octane for it today. I'm not too much into believing all the marketing hype so I just got decent oil, I think.
 

Zrt1200

Member
Jun 8, 2013
4
0
Why would you want to go to Race fuel unless you need it?? It will actually make your bike slower unless you need it to stop detonation from a modified cylinder & cylinder head.

The higher the octane rating the slower the fuel burns. That is why if you have say 16 to 1 CR ratio you need race fuel to stop the detonation. On a stock bike the slow burn time of race fuel will make you loose power.
 
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