J-Madd

I already have the powerjets, needles and billet bowls for these carbs. I also have another motor on alcohol with 39 mm carbs that Jeff set up. It looks like all you have to do is drill/tap a hole for the power jets and barb on the bottom of the bowl. I already know how to drill the dump tube and main jets. Is it that simple? Oh yeah, and what size bit and tap......... Thanks.

Supposed to be disked up dirt, not deep enough for paddles, I don't think....but I haven't seen it (the Piggott track) either.

Yep. I agree. The difference in my stock stroke Cub and my 4 mil Cub is unbelievable.

The shift drum itself is modified, and there are some differences on the gears themselves, but someone else will have to answer specific questions. I have no idea how it works, even though I installed it. There is a spring between the #1 and #2 shift forks, and springs between those forks and each side of the case as well.

Well, putting the override in with the cylinders still installed was not a problem. Just assemble the tranny in the bottom case half, then have someone help you put the the top in place. I'm not completely finished yet......I still have to put the clutch basket on, but it shifts through every gear and turns smoothly. I was lucky I decided to do this........the clip on the idler gear (the one the kick starter gear turns) came off and beat up the outside of my clutch basket. I used an e-clip instead of a snap ring....bad idea. The basket is billet, so it really didn't damage the surface where the clutch plates touch. It looked like glitter everywhere. The bearings all seemed to be ok, though. I had been using Klotz Flexdrive oil and changed it often. Here is also an observation I'd like to pass along: Don't try to use a modded shift star with an override. Just use the one that is already installed. I thought I'd put mine on the new shift drum for whatever stupid reason....and almost put it together that way before noticing that neutral is not in the same place and that there are not 6 notches. I already knew that it was 1-5 neutral down, but didn't really think about the shift star playing a role in that.

I'm sorry but I have to disagree....although I do agree that Banshees almost never overheat unless they've made several passes in a row drag racing, climbing hills,or are extremely lean. If the head gasket was leaking, coolant would leak into the cylinder, putting out the spark.

Jeff uses 0.012'' thickness base gaskets on 421 Cubs.......just talked to him yesterday about one. Also.....I have an extra set of stud extenders if you need them fast, pm me. If this is a brand new Cub, do you have the water plugs?

I'd like to add.....if you're running top speed its not even safe to hold WOT for a few seconds, let off, and go back to WOT. I locked mine up like that. I'd let off the gas for a couple seconds in between WOT bursts to let the bowls fill up (so I thought).....didn't work. I don't know it the bowls actually ran dry, or it leaned it out (so I've heard) when you go WOT, off the gas and WOT again.

The way I usually get stripped screws out is by using a dremel to cut a groove in the head of the screw and use a flat blade screw driver to get it loose then throw the p.o.s. screws in the trash. Vice grips may work as well.

The stator could have come loose and be rubbing the flywheel, giving the impression that it's seized. I've seen it happen before....other than that, yeah it could be crank bearings.

No problem about getting off track :cool: I started this thread several days ago with no replies and I look today and there's 23!! I'm gonna run 0.124 dump tubes and mains, 60 pilots, powejets all the way out, needles in the middle (EGN) to start. I'll let ya'll know. I won't have an override for another week so I won't be able to get all of the power to the ground yet.

NOTICE: I posted the wrong dates. September 15th there will be a 300 ft dirt drag racing in Piggot, AR at the fairgrounds...probably sign in and and test and tune until noon or so, then race. In Kennett the races will be September 22nd and October 6th.

This would be our 2nd and 3rd events. Hoping to have a good turnout. The approximate address is 901 E. South Bypass Kennett MO 63857. The location is behind the building at that address. We will open at 9:30 and probably race around 1:00 or so.

I've got three boxes full of broken YFZ parts that say both of my Banshees are more reliable than my 3 YFZ non functioning motors :yelrotflmao: :yelrotflmao: . However, the some YFZ motors are junk and prone to failure anyway up to the 2006 year models imo. I know people that have countless hours on 04 models that are fine, but they may have just been put together better at the yahama factory..........maybe on a day when no one was hung over. :tongue:

Are you holding the throttle open and kicking it until the gauge stops?? At 60 psi, it should run like crap.

I didn't know there was such a thing. Those would be great! I can't even start mine up at home without feeling guilty with non silenced OOFs...........ya know......wakin' up the neighbors' kids and all. I gotta check those out.

I understand. Thanks for the explanation. It won't matter as much now b/c I just bought a 1-5 dunable override. I've got more confidence in that now than I did when I posted this topic. Thanks!!!! :beer:

Thanks all!! :beer:

When I searched it was mentioned that the cases needed to be sent out for the duneable override so it could be tested......maybe that depends on who built it??. Now that the duneables have been around a little while, are they holding up and do they shift as well as the full overrides? I was recently told that the duneables in general don't shift as well and aren't the way to go if you're mainly drag racing. I already have a lockup, and it shifts ok now, but I'm going to alcohol any day. Thanks.

Thanks, that's what I thought. About riding with an override.........if your just lugging it to get to the track or drag racing area, how do you manage to do that without damaging the shift forks? Say I'm putting along in first gear and have to let off of the gas, so I pull in the clutch. When I get ready to accelerate again, do I have to rev it up and pop the clutch to keep from back loading the transmission?

I'm probably gonna get an override (non duneable) tranny. I thought I had heard that you can spilt the cases to remove the transmission and shift drum without taking the top end apart. Just checking to see if this is true or not. I mostly drag race with this motor and not sure about a duneable and having to send my bottom case off for a few weeks......I have 2 races to go to in the next month and need it done before then. Thanks.

On stock carbs? Thats odd. You can run a stock pilot in stock carbs with pipes and a filter (even porting) without being way too lean (unless its REALLY cold outside), assuming the air screw is adjusted accordingly.

The timing may be off if it backfires while trying to idle. I don't think a lean pilot would cause one to backfire, it just wouldn't idle at all.

Just look in the yellow pages for the nearest machine shop. Tell them to take 20 thousandths off of the head and your good to go!

Got some 39mm alky carbs from Jeff. He gave me some nicknames of a couple people with the same setup, but I forgot them. Any help would be appreciated, as well as any info about going to alky. I already know about purging, different plugs/gap, and oil ratio. Anything else? Thanks :beer: