Oregon dunner

I know of a few other guys that use a 152 to 155 on there ported cubs. It seemed to like leaner jetting once I got the cylinders ported.

In my opinion every motor is a little differnt.

152 main jet. 52 pilot, cel needle in middle clip. It's running over 90 hp on the dyno. When the air temp gets alittle cooler I will put a 155 in. 158, 160 and 162 were way to fat for my set up.

I am on the Oregon coast and I have a 421 with a 152 main, needle in the middle clip not sure on the air screw. 35pwk. I have 19cc domes, VF3 reeds with suffers. My cylinders are ported by HJR with a aggressive port job. I have cpi in frames and I am running +7 timing and c12 fuel. My bike has been tuned on a dyno and runs really good. Cam at Redline did the work.

here are some pictures of my plug chops . Looks real rich to me

I am having some jetting issues and I think I am getting real close on where I need to but have a few questions and looking for some suggestion to try for the next time I go out. My Current Mods. 4 Mill 421. CPI in frames. I have a aggressive port job on my cub cylinders by Kevin at HJR. 19 cc domes and + 7 timing. I am running 35 pwk carbs and my current jetting after today is 52 Pilot, Cel needle on 5th clip from the bottom. My needle is all the way down. I have a 160 main. The elevation is at sea level. I have only a couple hrs on this motor. I started my day off with a 52 pilot. The needle was 4th clip position and a 160 main. I had a bawg down low and did not know if it was a lean or rich so I did a plug chop with 2 wfo runs. I put different plugs in and continued to ride and try different settings. I felt like topend was good and maybe could go to a 162 main. I started to mess with the needles and I raised it up a few clips and 1.5 turns on the air screw. The bog got worse. I went back and dropped the needle all the way down. 1.3/4 turns on the air screw. I raced it thur all the gears and the bike felt real good thur all gears. I feel like I could go leaner down low but I feel like I should not have the needle all the way down. Is this because my pilot setting is to rich or maybe even my main? or do I need a leaner needle? The bike flat out rips and has power everywhere and pulls really hard and long up top. I came home and cut the plug apart and I had a light brown color on the base. I am thinking I am real close but not sure. Any suggestions? Thanks

just had to share one more of my seat cover all fitted and installed. Thanks Jeff

My new cover. Just need to fix my seat foam.

Hi guys, I am just wondering on where people go to buy replacement seat foam so I can put on my new seat cover by Vegas. Thanks

I fill up 65 to 70 gallons of diesel a week in my work truck and aux tanks. Its hwy robbery if you ask me.

I am down for meeting up!

I am not married and have no kids. I am a Pilebuck Foremen and certified structural welder for a bridge construction Company.

I run VP c12 in my 421 and +7 timing. My bike runs a little cooler the when I was running 110. U4.4 is a great fuel. You have to bump up your jetting a little bit to run it. Great fuel. Same price as c12.

I run +7 and c12 fuel on my 4mill ported cub. Runs really well. I dont drag race a lot but I do run it pretty hard on the dunes. Its still running.

HJR did a great job on my cub cylinder. :headbang:

Sent you a pm

Hi. Do you still have the plastic for sale? Colin

I have ran it at the drags with a 155 main. Seems to run fine.

I come to the coast all the time. I usually ride my CRF 450. When I get tired of the that I head to the steep tree shots or Idiot holes right next to the water. This is what my banshee currently looks like. Soon to have white plastic with some paint.

Thanks guys. I dropped my pilots back down to 50 and I went up to a 160 main and 1.5 turns out. I will see what happens when I head back out to the dunes.

Hi guys. I am wondering on pilot size with porting. Is it common to go up in pilot size when you get a aggressive dune/drag port on a cub cylinder. Whats the best way to determine the pilot jet? how may turns is to much or not enough? My current setup is a 4mill 421, 35pwk, 52 pilot, 155 main and I think the needle is 3 clip and I am running + 4 timing I am at sea level on the Oregon coast running HJR porting

I have 35 pwk carbs with a 52 pilot and 155 mains and no clue on what needle i have. My current mods are 19cc domes, 4 mill crank and of course cub cylinders with a aggressive dune/drag port and port match case by HJR. I am running +4 timing and cpi inframe pipes and riding at sea level.

I was wondering if there was a topic about 4mill 421 cub jetting? Thanks

I will probably put in a billet gear and what ever else needs to be fixed. The fucked up part of it is. I just broke in the motor and did not even go through 5 gallons of gas. The tranny looked good and the only thing I replaced was a shift shaft, nylon bushing and spring and adjuster bolt.

I dont have time to work on it so I am thing of bringing it to your shop and having you check it out.