HELP!! 1983 honda ATC 250r w/ 309cc kit SLUGGISH!!

[ricmonro4]

Hey peeps,

Trying to figure out what's wrong with my bike.

Got an 83 250r that has a 310cc big bore kit on it. I got the bike like this.

THE BREAKDOWN:
I got it about 2 months ago. It turns on and runs superb in neutral, revs up nice and crisp and sounds nice and peppy. It has the big bore 310 kit, with a bigger, flatside carb, and looks like a custom built fatty exhaust. I took it out, the first time, to a dirt place and it ran good and strong but I felt like it wasn't all there in the top end. 1st and second gear rev up fine but when in 3rd it revs up but sounds like it's bogging out. Had to wait a couple of seconds on flat ground for 3rd gear to rev up. Same for 4th and 5th gear. So I thought maybe a nice carb clean and a new plug would fix it .

So I cleaned the carb and changed the plug to the common BR8ES NGK plug that is used in the regular 250r and everything sounded good. Didn't really ride it around and gun it since didn't have enough time to test it before our Glamis trip.

So I took it to glamis, and it did the same thing but now it was much more noticeable. The only way I could climb the medium size dunes was to make the motor scream, if I didn't it would bog out and lose power very quickly. Needless to say, it couldn't even go up the big dunes. My cousins were with me with there 250r atc's and they would climb these dunes like nothing. I figure since I have the same year and a big bore kit I would be able to smoke them but that didn't happen. Haha.

HELP PLEASE!! ANY advice would be greatly appreciated! !

I am thinking that carb is too big for that carb, or maybe not the right plug. Maybe the exhaust. My buddy is telling me to go back to the stock carb and fatty exhaust. I've seen in chat rooms that ppl still use the stock carb and exhaust on the 300 big bore kits.

[sledcrazyinCT]

what is the compression reading?

[ricmonro4]

I believe last time I checked it was around 120

[ricmonro4]

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This is the bike.

[250rRoostmaster]

I believe last time I checked it was around 120

120 psi is a little low.

[ricmonro4]

You're right my cousin was the one that checked that and he said it was in the 150's. I have horrible memory. Haha

[sledcrazyinCT]

Check it again, it could have dropped since your cousin checked last. Honda calls for a rebuild if under 128PSI

[ricmonro4]

Okay i will check it .... I'm no expert but wouldn't it not turn on, idle properly, and rev up properly if it was a compression problem ?

[ricmonro4]

I was thinking it was more of a jetting problem. ?? But I will take all the advice given and give it a shot.

[hatc200x1]

Pull the plug and see what color it is. The main circuit might be a little rich.

[ricmonro4]

That's what I'm gonna do when I'm gonna check the compression. I found this to check the jetting: http://www.3wheelerworld.com/archive...p/t-55086.html

[250rheath]

That is nice looking hondaline 300 topend

[ricmonro4]

Ahhh it's a 300 hondaline kit! Thanks! Makes a lot more sense.

What do you guys think about that carb? Does it need that carb or should I just go with a stock carb and get the bigger main jet?

[sledcrazyinCT]

When you cleaned the carb did you notice the jet size currently installed? Also do you have the plug you replaced that originally was in the ATC when you bought it? If so that can provide some answers to how close it was jetted before you bought it.

[BOB MARLIN]

A low compression engine will start and idle just fine. It will just lack power.