PJ38 Choke Question

[CR500PHIL]

I have a stock PJ38 on my CR500 engine in my AF. It takes many kicks (20+) to start cold but runs great once started and starts great when warm. It seems the choke is not functioning. Also when I turn the choke knob to adjust the idle it has no affect on the idle speed. When I turn the knob counter clockwise to increase the idle the idle speed stays the same but the knob rises into the choke on position. Does this sound like I need a new choke valve for the carb or has this behavior been seen before?

[south central hoon]

I think you are answering your own question. replace it. the PJ choke circuit is pretty weak to begin with.

20 kicks? that is unreasonable.....

mine starts first kick all the time. three or four primers and give it hell. lights everytime.

[CR500PHIL]

You won't start any dirt bike first kick here - not too warm here yet. That being said I would expect 3 kicks like my YZ250. I have another choke assembly on the way - the guy I bought the carb off on eBay is going to send another free of charge - nice guy.

I think you are answering your own question. replace it. the PJ choke circuit is pretty weak to begin with.

20 kicks? that is unreasonable.....

mine starts first kick all the time. three or four primers and give it hell. lights everytime.

[CR500PHIL]

Ok well my choke problem is more than just a the choke rod. I was sent another by the guy I bought the PJ38 carb from and it is in mint shape. I also cleaned the entire carb. I put fresh gas in the bike too. I start the bike and it requires more kicks than it should. Once running the bike runs perfect and once going starts first kick afterwards. The strange thing is applying the choke has no effect while the engine is running - does not increase RPMs or anything. Since the choke is the idle adjustment, the idle adjustment has no effect either. Basically it seems I am starting the running without a choke even though I apply it. FYI I am running the bike without an airbox / filter now since I still have the bike on the jack in my garage - could this have an effect? Also is it possible that the fuel height is too low for the fuel to "reach" the starter jet? This is very strange.

[honda02]

I been having the same problems Plus once I get it running it willn't Idle very well either I had a CR250 with the PK carb it worked fine.

I just picked up a PWK 38 off Flee bay for $45.00 I hope this helps out if still hard to start after the new carb I going to get a compression release.

I also notice the motor not getting gas is the reason It's been so hard to start it's the choke on the PK Carb.

What I have read the PWK is easyer to get set up.

[dannygraves]

pilot circuit. start playign with your air screw, too rich and too lean will cause hard starting, but too lean will usually make a really high idle while too rich will make it so the air coming in through the idle adjustment isn't enough.
turn your airscrew in some and try again.

[dannygraves]

the lack of airbox would lean it out some. what pilot jet do you have and how many turns out is your airscrew?

[CR500PHIL]

the lack of airbox would lean it out some. what pilot jet do you have and how many turns out is your airscrew?

I am running 170 main and 55 pilot. The needle is 1369 as opposed to 1370 which would richen things up a little I believe. I was thinking perhaps changing the clip one position to lean it up a little to counteract this but being a novice I am nervous. My bike sounds the best with the air screw out 2.5 turns. When warm the bike starts first kick everytime. What about the cable adjustment on the top of the carb - how do you set that - I am speaking on the small cable length adjustment on the PK carb. Could this have an effect? My choke still has no affect on engine at all. I even checked the float height which is dead on at 16 mm. When I am driving mine it seems weak on top - like the bike is no "opening up" and getting on the pipe properly. On the low side the bike seems much better but I am still not sure if it is running like it should. I also got to say that besides cold the bike is very easier to start once I learned the drill and do a full stroke, forcefull kick. I do not even have to jump to start it - I just use leg strength.

[CR500PHIL]

the lack of airbox would lean it out some. what pilot jet do you have and how many turns out is your airscrew?

I am running 170 main and 55 pilot. The needle is 1369 as opposed to 1370 which would richen things up a little I believe. I was thinking perhaps changing the clip one position to lean it up a little to counteract this but being a novice I am nervous. My bike sounds the best with the air screw out 2.5 turns. When warm the bike starts first kick everytime. What about the cable adjustment on the top of the carb - how do you set that - I am speaking on the small cable length adjustment on the PK carb. Could this have an effect? My choke still has no affect on engine at all. I even checked the float height which is dead on at 16 mm. When I am driving mine it seems weak on top - like the bike is no "opening up" and getting on the pipe properly. On the low side the bike seems much better but I am still not sure if it is running like it should. I also got to say that besides cold the bike is very easier to start once I learned the drill and do a full stroke, forcefull kick. I do not even have to jump to start it - I just use leg strength.

BTW - this is with the bike fully assembled with air box and new oiled Uni filter.

[CR500PHIL]

pilot circuit. start playign with your air screw, too rich and too lean will cause hard starting, but too lean will usually make a really high idle while too rich will make it so the air coming in through the idle adjustment isn't enough.
turn your airscrew in some and try again.

Could this also cause the choke to have no affect on the engine when the bike is running or being started?

[CR500PHIL]

I may have said that wrong - not sure if my needle is 1369 or 1370 but I know when I looked in the manual I had the needle that was listed in the richer list for optional needles - not the stock needle.

[dannygraves]

have you tried it at 1 1/2 turns (stock)

[CR500PHIL]

have you tried it at 1 1/2 turns (stock)

I have and it did not seem to respond as well as lower speeds. I have the bike ready to try again. I just put a 175 main in it (from 170) - if the bike blubbers on the high end I will know this is too rich. I am having a hard time figuring out if the bike is lean on the top end but it does not seem rich - very whiny sounding - not blubbering but not surging either. I have the bike ready to test again - hopefully this weekend I will get some time to do more testing with it. If this makes everything worst I am thinking go back to 170 main and try one clip position leaner and go back to 1.5 turns on the air screw to try.

[dannygraves]

yeah, I haet PJs, the choke/idel setup never works quite right...

[CR500PHIL]

yeah, I haet PJs, the choke/idel setup never works quite right...

It seems like a "process of elimination" setup. LOL I am tempted to replace it and I may. Have you ever seen them where the choke has no affect though - weird. I mean it the starter jet is opening and has fuel I would expect it to have an effect.

[MojoScojo]

yeah, I haet PJs, the choke/idel setup never works quite right...

It seems like a "process of elimination" setup. LOL I am tempted to replace it and I may. Have you ever seen them where the choke has no affect though - weird. I mean it the starter jet is opening and has fuel I would expect it to have an effect.

Only if you are already close.

[100hp honda]

the problem with a pj is most guys dont understand how they work, so they think something is wrong with it. im guessing your jets are so far out of whack and thats whats causing your problem. ive used pj and pwk in the past and both work great. im currently using a pj and it works flawless. better get a book and read up on how the carb operates

[CR500PHIL]

yeah, I haet PJs, the choke/idel setup never works quite right...

It seems like a "process of elimination" setup. LOL I am tempted to replace it and I may. Have you ever seen them where the choke has no affect though - weird. I mean it the starter jet is opening and has fuel I would expect it to have an effect.

I reread you post and I think I see what you mean - air screw can regulate the amount of air in idle circuit - causing my no affect idle adjustment - I am beginning to hate PJs too. It seems much more logical to have the idle adjustment move the slide slightly like the PWKs.

[Travis]

My choke has minimal affect. The bike will run with it on but not as good. It takes a few kicks to get it started but starts fine afterward. I just deal with it because taking the carb off requires time that I could be riding.

[coley13]

yeah, I haet PJs, the choke/idel setup never works quite right...

It seems like a "process of elimination" setup. LOL I am tempted to replace it and I may. Have you ever seen them where the choke has no affect though - weird. I mean it the starter jet is opening and has fuel I would expect it to have an effect.

It seems much more logical to have the idle adjustment move the slide slightly like the PWKs.

thats a method of poor tuning unfortunatly to mask other problems that are apparent and can lead to other jetting problems and then you would forever be chasing your tail trying to sort it

[CR500PHIL]

I been having the same problems Plus once I get it running it willn't Idle very well either I had a CR250 with the PK carb it worked fine.

I just picked up a PWK 38 off Flee bay for $45.00 I hope this helps out if still hard to start after the new carb I going to get a compression release.

I also notice the motor not getting gas is the reason It's been so hard to start it's the choke on the PK Carb.

What I have read the PWK is easyer to get set up.

Could you post whether or not the PWK worked out better? I am thinking about changing as well - then I will enlist the help of the 12 lb sledge hammer to fix the PJ.

[CR500R7]

[CR500PHIL]

My choke has minimal affect. The bike will run with it on but not as good. It takes a few kicks to get it started but starts fine afterward. I just deal with it because taking the carb off requires time that I could be riding.

The problem is in fall here it maybe 40 degrees in the morning - makes for hellish starting without a proper choke.

[CR500PHIL]

the problem with a pj is most guys dont understand how they work, so they think something is wrong with it. im guessing your jets are so far out of whack and thats whats causing your problem. ive used pj and pwk in the past and both work great. im currently using a pj and it works flawless. better get a book and read up on how the carb operates

My manual does not really tell how to set it up - it rather spends most of the time speaking of the different circuits but does not tell about the interaction of the choke / idle circuit and the air screw etc. The troubleshooting section says nothing about if the choke is not functioning. I just find no need to make things more complicated than they need to be. To me an idle screw that pushes the slide up makes more sense and makes differentiating any problems easier.

[CR500PHIL]

It seems like a "process of elimination" setup. LOL I am tempted to replace it and I may. Have you ever seen them where the choke has no affect though - weird. I mean it the starter jet is opening and has fuel I would expect it to have an effect.

It seems much more logical to have the idle adjustment move the slide slightly like the PWKs.

thats a method of poor tuning unfortunatly to mask other problems that are apparent and can lead to other jetting problems and then you would forever be chasing your tail trying to sort it

Well this poor tuning worked - I put the 175 main in a bang the bike rips. The choke still does not work but the jetting is much better now.