81 or 82 250r woot!

**mohadib** · 07-07-2009, 10:12 PM

Thanks everyone. Just put in a new plug. Did about the same...but then!! It took off like a rocket after a minute. Then it promptly ran out of gas. This is similar to the first and only time before that it ran. Right before it ran out of gas it started hauling butt. Think this is a coincidence? Filled it back up and it ran poorly again.

I pulled the carb off today, the jets are nice and clean. I dont have any air filter on ATM, just the box and the metal element thing. The tank looks pretty clean inside.

I'll pull the muffler when it cools down. The pipe doesnt seat well at the engine. I can see a little leak there.

I compression tested and got 120. I'm at about 7K feet if that makes any differience.

Thanks for all the help!

Edit: thought i should mention I did the compression test while the bike was hot. THe manual says I should have between 142 and 165 cold...

**Lukeatc185** · 07-07-2009, 10:17 PM

try running it without the gas tank cap on.

**mohadib** · 07-07-2009, 10:28 PM

Good idea man

That didn't do it, but I pulled the fuel line off the petcock. As soon as the bowl got low the bike took of like a rocket. It was great! So.. does this mean my floats are not shutting off or are adjusted too high? Or...???

THanks Everyone!

**1984ATC200S** · 07-07-2009, 10:37 PM

going off my ski-doo 2 stroke knowledge, it seems like its running way to rich, then when its runs out of gas it leans out and does the death rev? clean the carb, and double check your mix ratio, is my best advice. also wouldn't be running it outta gas often, no gas--> no oil--> no lubrication--> no engine

**mohadib** · 07-07-2009, 10:42 PM

THanks. Whats the death rev? It seems to pick up and haul butt right before it dies. The jets in the carb are real clean. Ill try playing with the mixture screw. I should also mention that the carb is not the carb the bike came with. At least it doesnt look like the one in the manual. THanks Again.

**1984ATC200S** · 07-07-2009, 10:54 PM

death rev, bike/sled, rev's really high rite before it seizes, blows the engine in other words, not good. also happens if there is an air leak

**mohadib** · 07-07-2009, 10:57 PM

Ahh, I have not experienced that yet. I played around with the mixture screw. Started with 2 turns out. THen slowly took it more out. Didn't seem to help much. Any ideas? Thanks!

**RodKnockRacing** · 07-08-2009, 10:06 AM

well they had 27mm carb stock it sounds to me like your running to rich my buddy had a 32mm carb on his 83 250r with a 210 main jet and it ran fine double check your main jet size if its to big it will run rich 2 strokes always seem to be pain to get tuned right but dont give up on her

**mohadib** · 07-08-2009, 01:50 PM

Thanks for the information RodKnock. I cant make out the print on the jet, so I'm not sure what size it is. Today I played with the needle settings and mixture screw. Seems to run very mildly better when I use the groove nearest the end. I have screwed the mixture screw all the way in and out and inbetween. Can't seem to get any improvements. Cleaned the jets again today too. Whats the purpose of the brass tube with holes in it?

Thanks!

**atctim** · 07-08-2009, 02:22 PM

For sure you are running rich. Take your main jet to a wire wheel and clean it up good to get the number off it. If the main jet is too fat (too big) it is letting too much gas come in and throwing off the air to gas mixture. You really need to know the size of the main jet - or you could just buy a new main jet stock size and put it in there.

By you saying "right before it runs out of gas it runs great" means when it is getting less gas it runs better. This tells me wrong main jet!

Looks like you are on the right track and doing things in a good craftsman like way - not doing crap haphazardly like we have seen here in the past. keep up the good work.

Oh - BTW you gotta get rid of those trial pros once you get it running good!

**mohadib** · 07-08-2009, 02:28 PM

Thanks atctim. I will brush up the jet and see what I can learn. I have a used carb from an 81 250r at my buddies. Its the stock carb too. But he is in jail for 20 days! It all started when he got a DUI on his Raptor I guess lol. Anyway, Ill checkout the jet and see if I can get in contact (no pun intended) with my buddies girlfriend for my carb.

Thanks

**mohadib** · 07-08-2009, 04:03 PM

Ok, pulled the jet off my blaster and put it on the 250r. Didn't change a thing. So I then put the blaster carb on the 250r. Took a lot of screwing around but I got it to work. THe machine came alive!! Hauls all kinds of ass! Doesnt seem to have a 5th gear though :\ Thanks for all the help everyone! BTW - What is the metal thing sticking out on the main jet of the 250r carb? Looks to block a lot of flow.

**MTS** · 07-08-2009, 04:47 PM

That piston looks Trashed, on the intake side from what i can see in the vid, looks like it has run a long time with no air filter,

**mohadib** · 07-08-2009, 05:33 PM

It had no airbox at all when I got it. No clue how long it ran that way :\ New news: I think I killed it! Wont start and only has 60psi compression. Was 120psi last night. Thinking the pistion or rings must have failed. I'll open it up tonight and have a look.
At least I got to have 20 minutes of fun first!

**mohadib** · 07-08-2009, 07:13 PM

Got the top end off. The rings and piston look pretty bad. What is the tool I need to measure with to find out what size piston I need? On the cylinder, am I just looking for scratches our gouges? Thanks

Thread: 81 or 82 250r woot!

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