PWK 39mm jetting

[Rhino89523]

"We can press charges I got the whole thing on video"......so lame!! you punch an old man and he lights you up and now you want to press charges. Great clip. glad that old man beat his shit talking ass.

[AlisoBob]

Yup......

[saharamike]

Back to topic...

How do everyone like their pwk over pj stock carb?
My opinion - the pwk works really good in low rpm where pj would stall. Im amazed by pwk design BUT for some reason I feel that pj is a tad better in lowend performance though, barely noticable anyway. Im planning on to get pwk38 and 41 along with several needles.

And Im proud of this thread got over 700 views.
-saharamike

[mr500]

I can do whatever to my bike. I have spent about 50 hours on jetting and oil ratio in the last several months.
-saharamike[/quote]

50 Hours on jetting one bike

[lewisclan]

1st:Send me your new PWK 39 after you pull the needle & jets out of it.
2nd: Then buy an Airstriker 38 Ill cover the postage,
3rd ask what Bob's magic needle is
4th:buy a few jets 172 through 185 if you dont already have them with the lazy K stamp assuming you have a few slow jets on hand from your 39
5th: jet your bike to run 40:1 of your choice of oil I lean on the Bean
6th spend about 30-min on getting it dialed in.
7th Ride the piss out of it.

[saharamike]

Yes it included research, my thoughts on jetting, play with jetting on my pwk39. I have pilot jet from 35 to 65 and main jet 160 to 185. And 4 needles. After jetted proper, the bike has all the power I could ever ask for. Sometimes it scared me if i am not careful with throttle

And no i will not change anything on my bike, only jetting and carb. 32:1 is what my bike like the most.

Send me your airstriker and i'll test it out.

-saharamike

[Rhino89523]

PJ jetted right out of the manual works perfect for me every time, bike gets ridden from sea level to 11,000 ft or so. I'll pay the shipping on the pj.

[BrianPaul69]

I was a noob back then. I have discovered that anything pilot 48+ on my pwk39 will not start. 40-45 is spot on. 170-175 main are good, depending on temperature and humidity.

32:1 is very popular mixture ratio for cr500 believe it or not. Brian, you might be running too lean 50:1. Again all bikes are different. Dont listen to any oil techs crap, listen to your bike how shes running, too much or little smoke. Play with jetting.

And no, I chose not to get air striker carb. My bike is set up for low end-mid power.

Sorry I haven't been on in a while and missed all the fun I've been preparing for a possible move for work and it hasn't left much time for fun things. Anyway, I've been working on motorcycles most of my life and never close my ears to advice whether good or bad. Even with bad advice there is something to be learned and I find myself learning something new all the time. I'm always trying to fine tune my bikes and I saw something online that caught my attention. I decided to get in touch with the guy who was making the setup ( Ron - Pulse Engineering ) and he really opened my eyes to a lot when it comes to tuning. He is very articulate and knowledgeable when it comes to induction systems and tuning and made a lot of sense. Those of you who aren't familiar with him he can be found on e-bay (pulseusa) with his Pulse Technology setups. Just type in CR500 Pulse and there he is. He explained in extreme detail about how the 2 (and 4) stroke engines work against themselves. There are just so many factory that come into play when tuning it's amazing we ever get the engine running properly. If you finally get the tune up as good as its going to get then do a top end rebuild and the compression is back up and everything is sealing good the tune up just went out the window again. Every little thing like pipes, gas, oil mix, altitude, weather conditions and even the air filter affects the tune up and we sure aren't dealing with electronic fuel injection here. These carburetors haven't changed much over the past 50 or so years so all you have to work with is the needle, the pilot jet, main jet and slide changes to work with. Picking the right needle can also be a challenge and get expensive. Something I explained on here somewhere a while back that was explained to me was about the oil / fuel ratio and jet size. If you start tuning at 50:1 and get it running pretty good then change the oil mix to 32:1 you just leaned out the engine and even though you have more oil in the gas you have less gas and more oil passing through the main jet. This lean condition can cause damage to the engine unless you up the main jet size to compensate.

After talking to Ron I understand now that biggest thing we fight against when tuning is the pulses that are constantly blowing back through the carburetor and screwing up the whole flow of air / fuel into the cylinder. He also explained to me about Rad Valves and V-Force 3 reed valves. Then he got into detail about the 38mm quad vent air striker carbs. After talking to him many times I could tell he had years of experience with tuning through trial and error. First the air striker carburetor is not just a flat out race carb or whatever you are thinking. It is designed to be a very responsive, efficient carburetor due to the twin fins on the airbox side. I can't remember everything I was told right now but that carb directs the air right at the needle which makes it a much more desirable carb over the normal PWK. I was also told the V-Force reeds have a real innovative approach but pretty much threw physics out the window with their design. They change the angle of the reed petals and for some reason that causes them to leak which makes the bike harder to start and hurts low end performance. I had them on three bikes, a 99 CR80, my 95 CR500 which I then put on my 84 CR500 and my CR480. Every bike was harder to start with those reeds. The 84 CR500 was a monster to start with them and once started it ran good but did lack low end responsiveness. I put a rad valve on it and now it starts on the 1st or 2nd kick and I can tell the low end grunt is back. I also installed a 39.5mm PWK (non air striker) on it which made a HUGE difference over the stock PE carb. It was like a 30 year technological improvement. I only used that carb because I already had it from my 95 which I put Ron's pulse setup on. The 99 CR80 almost started by hand with the Boyesen reeds on the stock cage and the CR480 fired up on the 2nd kick. You may be thinking where I found a V-Force reed setup for a CR480. Well the 86-01 CR250 reed cage has the same bolt pattern as the 82-83 CR480 but there is a mismatch in the carb boot to the reed cage opening. The VForce3 cage has a small opening and the stock carb boot has pretty big opening so the air / fuel charge will be slamming right into the Vforce reed cage. Anyway I tried it and didn't like the results. I have a Rad Valve also from a CR250 but the pipe angle is totally wrong. I was going to cut the pipe off and re-weld it back on at the correct angle bit didn't want to damage the rad valve. I decided to just machine the pipe off and work with the rubber carb boot because I still have a major mismatch. So I can ride the bike I just put the stock reed cage back in with the Boyesen reeds and sure enough with 2 kick she fired right up. Oh yes I also changed out the PE carb with the stock PJ carb off the 95 CR500. I couldn't get the jetting right on the PE and only had 3 pilot jets to work with. Ron also told me that the PJ carb was a good upgrade because the choke also richens up the mixture.

I was very hesitant to buy this pluse setup 1 because it was expensive and 2 because all the tech talk in the world doesn't mean it's going to work that way. I want everyone to know I am not a sales person for Ron's product all I'm saying is that when it comes to tuning there is so much more going on than what we think we know. Finally I bought and installed Ron's (continuous flow induction) setup and to my surprise the engine started right up and ran PERFECTLY!!! I almost shit myself because with something like this it ALWAYS seems to be riddled with issues. Pretty much everything he told me was right on. The bike sounded smoother, idled smoother, I could ride in 1st gear at a low rpm and it didn't want to kathunk stall out all the time plus the throttle response is instant. He is also continually doing R&D and last time we talked he said he found a new needle that worked better. He sent me the needle, a ziptie racing air screw and drill bit with instructions on how to do all the upgrades. I was going riding the next morning but really wanted to test these upgrades out so I pulled the carb and got started. The needle was the easiest of course but I had to modify the slide arch to allow more air, then I had to drill out the orifice down inside the air screw opening looking in from the air cleaner side. Lastly clean it all up and put everything back together. My final thought that should have been my first thought was that it was now 2 AM, I was going riding an hour away in the morning and there was no way I could start this thing up at that hour to see if the mods were going to work. I ended up sleeping in a bit and didn't get the bike loaded till 10AM so before I put it on the truck I gave it two kicks, it fired right up and idled perfectly. I think it would have fired on the first kick but I forgot to take the exhaust plug out. At that point I decided I can trust the parts and all the information from Ron. Another thing about the pulse setup is the air screw is not just an air screw anymore. He has the 38mm air striker carburetor that comes with his setup modified so that the air screw richens or leans the whole mixture not just idle mixture. Now if you ride on a cold day or a hot day you can just tweak the mixture by turning the air screw. I'm sorry I can't explain it better but I can't remember all the technical stuff he told me. All I know from talking with Ron is the Rad Valve and 38mm Air Striker carb is the setup you want with or without his setup. If you have them already and are interested in his setup he can modify your parts and you just need his intake.

Well this got a little longer than expected so I hope your not dozing off by the time you get to the end

[iggys-amsoil]

Perhaps he's a big deal over there >>. www.humaniplex.com ...NSFW !!!

[mr500]

Quote
"I can do whatever to my bike. I have spent about 50 hours on jetting and oil ratio in the last several months. I tried anywhere from 24:1 to 50:1. I like 32:1 the most. My '85 cr500 run excellent, even can idle all day long."
(There's 12 hour's out of 50 gone in ideling)

(Of course the engine is going to run different- your changing the Air /fuel ratio Daaaaaaaaaa)

Quote
"I have no any further comment." (Bullshit)

Then...

Quote
"Something I explained on here somewhere a while back that was explained to me was about the oil / fuel ratio and jet size. If you start tuning at 50:1 and get it running pretty good then change the oil mix to 32:1 you just leaned out the engine and even though you have more oil in the gas you have less gas and more oil passing through the main jet. "

( You really explained that too...somewhere..)

[saharamike]

Brianpaul, you really should post new thread relating with pulse stuff. So it will get more attention rather than this thread. Good post. This thread might get lock.

The reason why I said I have no any further comment is because I kept cool instead talk smacking. Or it'll get ugly.

[lewisclan]

Get it Mike!

[saharamike]

YEAH!

:thumbup: thumbup: :thumbup: :thumbup:

[saharamike]

Just a picture of my cr500.



I called her "the beast".