250 The 1999 YZ250
- Thread starter Trfsrfr
- Start date
Thanks Mike.
I'm not seeing it in the manual, but I'll figure it out. Not sure I've been into the forks of this thing yet, but I'd have to go back and look at the old posts. I parked her for awhile while I ran that heavy-ass 400. So just now getting used to her all over again, like an old girlfriend.
I will say I love this thing, and dont see myself selling it, ever.
After 3 hours at the track I dropped the MJ today to PC specs of 168...I didn't seem to notice much difference. I dont feel like its running cleanly though. Seems to sputter up til about mid-throttle, then she goes pretty good.
I looked at the plug and its black and sooty, but I dont think its an accurate read cuz when I limped her back to the truck at the end of the day I was stuck in fourth. Same shifter issue with my sons 125.
But she's fast.
Getting the suspension set up has now become a priority I think. After bottoming the forks all day and having the front tire not stay planted, jumping ruts.
Thats probably me being a pansy though...
I'm not seeing it in the manual, but I'll figure it out. Not sure I've been into the forks of this thing yet, but I'd have to go back and look at the old posts. I parked her for awhile while I ran that heavy-ass 400. So just now getting used to her all over again, like an old girlfriend.
I will say I love this thing, and dont see myself selling it, ever.
After 3 hours at the track I dropped the MJ today to PC specs of 168...I didn't seem to notice much difference. I dont feel like its running cleanly though. Seems to sputter up til about mid-throttle, then she goes pretty good.
I looked at the plug and its black and sooty, but I dont think its an accurate read cuz when I limped her back to the truck at the end of the day I was stuck in fourth. Same shifter issue with my sons 125.
But she's fast.
Getting the suspension set up has now become a priority I think. After bottoming the forks all day and having the front tire not stay planted, jumping ruts.
Thats probably me being a pansy though...
Something as simple as tire pressure will have you climbing out of ruts.
The springs probably out of spec. I would comb eBay for a set of stockers. To be sure that you have oems but they also might be shot out after 20yrs of ghetto cruising.
You are looking to get .44kg springs.
Stocks are .43. According to Race-tech.
http://racetech.com/ProductSearch/12/Yamaha/YZ250/1999
Racetech will get you closer than you can for now and after using Factory Connection to set up my stuff for racing I’ll never go anywhere else again.
Jetting if you can go more than 2.5 turns out on the airscrew with no change in idle you need a smaller pilot. Also drop your needle 1clip (raise the clip up 1 notch) , but I think P.C. recommends another size. I like my pilot circuit just a hair lean for the soul reason I like the way it feels when rolling out of turns. Crisp with a blast of power.
The 99 was unbalanced with f/r springs. If the fronts are brought up to .44 they would be more balanced, but they also need a little revalving in the shim stack.
Bikes old, so it has probably seen it's day. New springs could help and bring it back but don't expect much more than fresh if not revalved.
Oil level is 5.0" from top or 135mm. you can play with oil level to see if it helps. Reducing the air volume by increasing the oil level (amount) can benefit.
Good luck and carry on.
Bikes old, so it has probably seen it's day. New springs could help and bring it back but don't expect much more than fresh if not revalved.
Oil level is 5.0" from top or 135mm. you can play with oil level to see if it helps. Reducing the air volume by increasing the oil level (amount) can benefit.
Good luck and carry on.
The bike is 20 years old, but I love everything about it, and plan on keeping it so I'll see what I can find for it. Not sure I want to start learning MX suspension theory though, it seems really complex.
I was thinking of dropping the needle one position, but it's in the stock location now, and I remember the headache it gave me before. Also remember melting down the kid's CR80...
To be honest, I dont know how the bike is supposed to sound or feel. I've only got 7 hours on it at this point. It's fast and it makes good power, just seems like it could run a little cleaner. Feels like its sputtering a little. Maybe I'll have someone else at the track with some experience ride it.
It's all good. I'm on the safe side of the mixture, and I got a bunch of new parts coming for it and the KX. And the temp in the garage is an acceptable 65 degrees
I was thinking of dropping the needle one position, but it's in the stock location now, and I remember the headache it gave me before. Also remember melting down the kid's CR80...
To be honest, I dont know how the bike is supposed to sound or feel. I've only got 7 hours on it at this point. It's fast and it makes good power, just seems like it could run a little cleaner. Feels like its sputtering a little. Maybe I'll have someone else at the track with some experience ride it.
It's all good. I'm on the safe side of the mixture, and I got a bunch of new parts coming for it and the KX. And the temp in the garage is an acceptable 65 degrees
According to Racetech.com I should have a .46kg;
If I go with Factory Connection I have the option of a .45 and can get these relatively cheap;
A Race Tech .46 option is also available...
And it looks like I need to change the rear spring too according to Racetech.com;
This stuff confuses me. How radically different would my bike be if I installed these? And If I put in the new front springs, must I also do the back?
If I go with Factory Connection I have the option of a .45 and can get these relatively cheap;
A Race Tech .46 option is also available...
And it looks like I need to change the rear spring too according to Racetech.com;
This stuff confuses me. How radically different would my bike be if I installed these? And If I put in the new front springs, must I also do the back?
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Go with what mike and Gary said and if they're wrong call them homos,
they won't steer you wrong and can be bothered to help you, you call racetech and they will tell you what makes you empty your wallet fastest with no care in the world about your thong giving you a wedgie with the .43
they won't steer you wrong and can be bothered to help you, you call racetech and they will tell you what makes you empty your wallet fastest with no care in the world about your thong giving you a wedgie with the .43
Two questions-
1 - I installed the new shift rod and lever last night; when I got to the track today the kickstart lever was making a chatter noise, as it was rubbing up against the gears. Is this because I didn't get the kickstart spring tang put in the correct position?
2 - If you recall I think I mentioned that I thought the bike was still running rich and was thinking about dropping the needle 1 position. Got to the track this morning, pulled the choke and let the bike warm up. Gave her a minute or two, then pushed the choke in and starting revving it and she died, wouldn't restart. I assumed I fouled the plug, and when I pulled it was wet.
Installed new plug, ran 4-5 laps, did a plug chop - threads were wet and porcelain was dark. Went to drop the clip, it was on the 2nd position, so I dropped it to the first. Bike seemed to run a little crisper. Did a plug chop at the end of the day, and here is the plug;
Does this still look too rich? I cant drop the needle anymore. The MJ is a 168 (stock 172), PJ either 48 or 50, float is dead nuts on, 32:1. 1250 feet altitude, temps we're around 55 degrees F.
It still seems to be a little snotty sounding in the upper rev's. Is that normal? I dont know, this is the first time I've ever had the bike running anywhere near what she's supposed to. She's fast AF, but I feel like I'm not getting all of it.
1 - I installed the new shift rod and lever last night; when I got to the track today the kickstart lever was making a chatter noise, as it was rubbing up against the gears. Is this because I didn't get the kickstart spring tang put in the correct position?
2 - If you recall I think I mentioned that I thought the bike was still running rich and was thinking about dropping the needle 1 position. Got to the track this morning, pulled the choke and let the bike warm up. Gave her a minute or two, then pushed the choke in and starting revving it and she died, wouldn't restart. I assumed I fouled the plug, and when I pulled it was wet.
Installed new plug, ran 4-5 laps, did a plug chop - threads were wet and porcelain was dark. Went to drop the clip, it was on the 2nd position, so I dropped it to the first. Bike seemed to run a little crisper. Did a plug chop at the end of the day, and here is the plug;
Does this still look too rich? I cant drop the needle anymore. The MJ is a 168 (stock 172), PJ either 48 or 50, float is dead nuts on, 32:1. 1250 feet altitude, temps we're around 55 degrees F.
It still seems to be a little snotty sounding in the upper rev's. Is that normal? I dont know, this is the first time I've ever had the bike running anywhere near what she's supposed to. She's fast AF, but I feel like I'm not getting all of it.
1: almost sure of it.
2: you’re doing the plug chop wrong but it looks fine and just bybthe look of the plug it appears that you are lugging it.
This is what it sounds like when you are really running the motor at the right rpm.
http://youtu.be/zQrifptAav4