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'96 yz250 Idle

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Is it normal to have to keep revving my '96 yz250 to keep it idling? If I let it idle without revving for maybe 5 seconds, it shuts off. It will restart again and stay running as long as I blip the throttle every couple of seconds. The fuel:oil mixture is 32:1. My buddies keep telling me this is normal. Most of my toys are 4 strokes, but I have had 2 stroke jet skis and I didnt have to keep revving them to keep them running. Previous owner rejetted the carb and Im wondering if the idle jet is too big. I just want to know if I actually have an issue of if my buddies are right?

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Thank you. I didnt realize I was posting in the wrong place.

Another question. Does a '96 yz250 have any kind of decompression lever or something to make it easier to start?

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No one knows if this thing had a decomp lever at some point in its existence?

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No one knows if this thing had a decomp lever at some point in its existence?

No, no decomp lever. Not that you could not fit something, but it was not supplied with one.

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I had the same problem with my YZ. Turned out to be a VERY EASY fix. Just tuned the idle by using the idle adjustment scew on the carb. Turn in and out till you get the bike ideling at your liking.

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I had the same problem with my YZ. Turned out to be a VERY EASY fix. Just tuned the idle by using the idle adjustment scew on the carb. Turn in and out till you get the bike ideling at your liking.

Youre very close. I fixed it already. The mixture screw was only turned out about 1/2 turn. I backed it out some more and adjusted the idle. I want to make more adjustments, but I dont have time right now. I didnt think it was normal for the bike to not idle, but my buddy insisted that it was.

As far as the decomp, I guess Ill tell my old lady that if she cant start it, she cant ride it :cheers:. I started it for her last night and she proceeds to go abotu 3" and stalled it, so I had to kick it again since she gave up after a couple of tries and not being able to push the kicker.

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... I didnt think it was normal for the bike to not idle, but my buddy insisted that it was...
I'm with your buddy.

These days it's more of a personal preference, but just about every 2-stroke I've seen has had the idle set so that it would die if not 'blipped'.

Sure, the carb can be adjusted so that the bike won't stall, but the norm was always to set the idle real low -- has something to do with racing or some such.

Not until 4-strokes became mainstream did dirtbikes idle. :ride:

My '96 was a bear to start (plus the head was milled) -- super stiff to kick. Much like an old BSA.

A comp release would really be handy if you can get one.

I loved my '96 YZ250. Hope you are happy with yours! :cheers:

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Hmmm my 96 is pretty easy to kick over I thought I read somewhere these bikes were low compression but I may be wrong.

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I'm with your buddy.

These days it's more of a personal preference, but just about every 2-stroke I've seen has had the idle set so that it would die if not 'blipped'.

Sure, the carb can be adjusted so that the bike won't stall, but the norm was always to set the idle real low -- has something to do with racing or some such.

Not until 4-strokes became mainstream did dirtbikes idle. :ride:

My '96 was a bear to start (plus the head was milled) -- super stiff to kick. Much like an old BSA.

A comp release would really be handy if you can get one.

I loved my '96 YZ250. Hope you are happy with yours! :cheers:

I dont use it for racing. Just some riding around. Its nice if it keeps running when I get off it and my old lady or buddy want to ride.

Where can you get a decomp and how would you install it on something that didnt originally have one? Sorry if these are stupid questions. All of my other toys are 4 stroke.

So far, I like my yz. It takes some getting used to, but its fun so far Ive only had it for 3 days and havent ridden it a lot yet.

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This bike does have an idle adjustment, but its tough to find.

The black choke knob turns and acts like an idle speed adjustor. Set it low, then adjust your airscrew for the smoothest idle and response.

THEN, adjust the choke-idle -knob to the speed you want.

The 96/97/98 yz 250 was fairly low compression compared to current models. But again, the head was poorly designed and the bike never really came alive until it was milled some. A used bike may have had this done, and probably did, by the previous owner.

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Hmmm my 96 is pretty easy to kick over I thought I read somewhere these bikes were low compression...
Like RCannon mentioned, the motors were kinda weak (especially the '96), so it seems like EVERYONE tweaked them somewhat, often times starting with raising the compression.

The guy who did my headwork raced a YZ at the National level. He could really make 'em fly. The compression was soo high, you had to start it like an old 4-stroke; push on the kick lever until it stopped (approaching TDC), then wind up and fling your weight down on the kicker.

If mike3800's bike is anything like mine, I wouldn’t want to mess with any lady who could start it!

I have no idea where to get a comp release, unless you machine another spark plug hole into the head and get the screw-in type. :cheers:

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Like RCannon mentioned, the motors were kinda weak (especially the '96), so it seems like EVERYONE tweaked them somewhat, often times starting with raising the compression.

The guy who did my headwork raced a YZ at the National level. He could really make 'em fly. The compression was soo high, you had to start it like an old 4-stroke; push on the kick lever until it stopped (approaching TDC), then wind up and fling your weight down on the kicker.

If mike3800's bike is anything like mine, I wouldn’t want to mess with any lady who could start it!

I have no idea where to get a comp release, unless you machine another spark plug hole into the head and get the screw-in type. :cheers:

I would guess some work is done to the bike. Im 200 lbs and sometimes the kicker comes to a dead stop when I try to push it down and it hits compression.

I might tell my slightly less masculine friends that they can only ride the bike if they can start it.

I dont think I want to get in to machining anything. Ill just have to grow a pair and quit whining.

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I would guess some work is done to the bike. Im 200 lbs and sometimes the kicker comes to a dead stop when I try to push it down and it hits compression.
Damn! It sounds like you have my old bike!
I might tell my slightly less masculine friends that they can only ride the bike if they can start it.
:cheers:

There is an upside to everything.

It's an anti-theft device!

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I recently got an 98 yz250 and starting this thing has ruined my boots. Boot hit the peg at the bottom of the stroke. I have tore the sole and side all up :cheers:

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Not trying to jack your thread but can you do the head milling yourself or would it be better to send it out somewhere? I really need to get this done on mine if it makes that big of a difference.

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Not trying to jack your thread but can you do the head milling yourself or would it be better to send it out somewhere? I really need to get this done on mine if it makes that big of a difference.
Well, if by "big difference" you mean "more difficult to start", milling the head will get you that! :cheers:

I'd check with RB or Eric Gorr for a recommendation first. There appears to be a lot involved in modding a head correctly.

Some threads on head work..

http://www.thumpertalk.com/forum/showthread.php?p=10197463#post10197463

http://www.thumpertalk.com/forum/showthread.php?p=9484435#post9484435

Good luck!

For the OP, some info about a compression release...

http://www.accu-products.com/accu-products/accu-start-compression-release-kit/prod_3015.html

http://www.tboltusa.com/store/ez-de-comp-by-frd-fits-all-pit-bikes-p-1304.html

http://www.thumpertalk.com/forum/showthread.php?p=8971491#post8971491

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Thanks for that info Dan much appreciated would give you some rep but it figures have to throw some around before I can send it your way. My bike has never pinged or detonated so would it be worth getting the head reworked?

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Honestly, I'm not sure about the '98; it was a unique bird. It had what seems like a 'one-year' motor -- different (and better) than the '96 & 7, yet unlike the '99 & up motors. :ride:

I think RCannon and a few other members are familiar with it, that's why I mentioned contacting EG; he would know for sure. :cheers:

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Mines a 96 she runs really well was just curious about the head mods. Thanks.
Whoops! I guess I got you mixed in with ben williams' post. :cheers:

The '96 needed a lot of work to make competitive. They run great, but almost everybody felt it could use some extra zing.

Upping the compression by shaving the head is probably the cheapest, best bang-for-your-buck thing you could do, but it won't turn it into a tiger.

But there have been advancements made in head mods recently that go beyond just raising the C.R., so who knows?

Porting, piston mods, V-Force reed cage, and the wonderful long-rod kit is what it took to make the '96 a contender.

These guys seem to know the '96 YZ250 pretty well.

http://www.surfnturfracing.com/customyz.htm

Good luck!

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