New JL250P from Tejas!

[NSTMIKE]

Originally Posted by BigBad250

Well... Devoting a weekend to working on the bike almost went down the drain... The chain popped off while I was on the highway! Scary stuff!! But I at first thought the transmission was shredded, none of the gears worked and all I heard was metal on metal grinding, but it was a slight relief to find out that it was only the chain! I have from now until midday Sunday to take the bike apart and fix everything that I find wrong with it! I'm not sure if I should post pictures here or in a new thread? What do yall think?

LET THE COUNT DOWN BEGIN!!

WHOA! Not good. Hopefully you're safe and the bike is ok. How/why would a chain pop off?!

Maybe start a new "build thread" and post pics etc. I am thinking about doing the same to cover the things I've been doing and will do moving forward. I'm very interested in seeing your progress, as we share a very similar bike.

Best of luck

[BigBad250]

Originally Posted by NSTMIKE

WHOA! Not good. Hopefully you're safe and the bike is ok. How/why would a chain pop off?!

Maybe start a new "build thread" and post pics etc. I am thinking about doing the same to cover the things I've been doing and will do moving forward. I'm very interested in seeing your progress, as we share a very similar bike.

Best of luck

Heres a little teaser from my adventures today!

[culcune]

Originally Posted by NSTMIKE

How/why would a chain pop off?!

Are these bikes' back wheels as easy to move forward or backwards as easy as the enduros? Was the chain stretched to beyond useful/need a new one?

[BigBad250]

Originally Posted by culcune

Are these bikes' back wheels as easy to move forward or backwards as easy as the enduros? Was the chain stretched to beyond useful/need a new one?

The chain came off due to the adjusters not being tight, but yes it is fairly easy to adjust! It was almost the exact same as all my previous dirtbikes would've been adjusted. Most people use a rear axle stand to adjust it but I had no problem leaving it on the kick stand. Just checked the distance between the axle and swingarm mount on both sides!

There's hashmarks on both sides of the swingarm that help get the axle mostly lined up, but it's always a good idea to check by measuring!

The chain seems fine for now, but I will most likely replace it fairly soon so I have an excuse to buy a new sprocket!

[NSTMIKE]

Originally Posted by BigBad250

The chain came off due to the adjusters not being tight, but yes it is fairly easy to adjust! It was almost the exact same as all my previous dirtbikes would've been adjusted. Most people use a rear axle stand to adjust it but I had no problem leaving it on the kick stand. Just checked the distance between the axle and swingarm mount on both sides!

There's hashmarks on both sides of the swingarm that help get the axle mostly lined up, but it's always a good idea to check by measuring!

The chain seems fine for now, but I will most likely replace it fairly soon so I have an excuse to buy a new sprocket!

Good info

[BigBad250]

Originally Posted by NSTMIKE

Good info

Does your bike have the EGR doodad? Since my bike has dual exhaust, I had 2 of them but they weren't hooked up to anything! The tubes from the egr units were just tucked up under my gas tank, there's also a connector near my seat that isn't hooked up to anything.. Still trying to figure out what it could possibly be! I definitely recommend taking off all the plastics and making sure EVERYTHING is hooked up!

And I also have the carbs running wide open, no airbox hooked up.. I've noticed a decrease in performance. And by "decrease" I mean at WOT it tops out at 7K rpms and it just feels really laggy. I'm assuming it's because it is now getting too much air and not enough fuel? I figured the jets were designed to be used with the restriction of the air box. Can anyone verify this for me?

[SpudRider]

Originally Posted by BigBad250

...And I also have the carbs running wide open, no airbox hooked up.. I've noticed a decrease in performance. And by "decrease" I mean at WOT it tops out at 7K rpms and it just feels really laggy. I'm assuming it's because it is now getting too much air and not enough fuel? I figured the jets were designed to be used with the restriction of the air box. Can anyone verify this for me?

I suspect you are correct. I suggest you install the next size larger main jet, and see if engine performance improves. If so, continue installing the next size larger main jet until the performance stops increasing.

[Weldangrind]

Originally Posted by BigBad250

And I also have the carbs running wide open, no airbox hooked up..

What are you using for air filters?

[BigBad250]

Originally Posted by SpudRider

I suspect you are correct. I suggest you install the next size larger main jet, and see if engine performance improves. If so, continue installing the next size larger main jet until the performance stops increasing.

Well it seems to be better, I took the gas tank off and found I had a vacuum leak! Plugged the hole and it seems to be doing great now! But I did end up putting the box back on until I can get a couple Uni filters and bigger jets! But is there any size jets you could specifically suggest (main and pilot)?

[BigBad250]

Originally Posted by Weldangrind

What are you using for air filters?

I was just running the carbs with no filters just messing around, but I know it's not good for the engine so I went ahead and tossed the box back on!

[SpudRider]

You either need to install the original air box, or add external air filters. If you ride the bike without air filtration, you will add dirt to the fuel/air mixture entering the engine. This dirt will damage the intake valve and its valve seat, causing the valve to recede into the cylinder head. You can only experiment with carburetor jets after you have installed a good air filtration system.

[Weldangrind]

Originally Posted by BigBad250

But is there any size jets you could specifically suggest (main and pilot)?

Start with two sizes bigger than stock for starters.

[NSTMIKE]

Originally Posted by BigBad250

Does your bike have the EGR doodad? Since my bike has dual exhaust, I had 2 of them but they weren't hooked up to anything! The tubes from the egr units were just tucked up under my gas tank, there's also a connector near my seat that isn't hooked up to anything.. Still trying to figure out what it could possibly be! I definitely recommend taking off all the plastics and making sure EVERYTHING is hooked up!

And I also have the carbs running wide open, no airbox hooked up.. I've noticed a decrease in performance. And by "decrease" I mean at WOT it tops out at 7K rpms and it just feels really laggy. I'm assuming it's because it is now getting too much air and not enough fuel? I figured the jets were designed to be used with the restriction of the air box. Can anyone verify this for me?

Interesting. Was your EGR bolted up on your exhaust pipe, close to where it bolts up to the engine? That's where mine is and there's definitely a tube/hose attached to it. I'll be taking off the plastics soon to check on stuff, I'll let you know where the other end goes on mine.

Also, my bike has no air box. I do have a small filter attached to the end of my carb. Was yours different? Pics?