Ducman

We can ride right out of the house driveway to access the dunes. We do have to go through the Discovery Point campground, but if they have their gate closed, we can probably get away with riding 200 yards down the county road to the dune access sand road. But if the riding area is closed, we're screwed.

Sup Ya'll? It's been a good while since I've made any posts in BHQ, sorry for my absence. Does anyone have any info on the Oregon dune riding areas? Will they stay open? We have MiCasa reserved for 5 days in early May at Winchester Bay. I'm hoping we don't have to cancel our trip due to the dune riding area closure. We'll make sure we ride at least 6 feet apart for social distancing unless we're drag racing up Banshee hill, then all bets are off. I'm pretty sure the alcohol will poison my liver and kill me before the corona does anyway. I figured I'd ask, since I just heard that they are closing Sand Mountain in NV. Thanks for any info you may have.

dito on the 421 seval and Redline. You probably don't need a 4 mil serval for the kind of riding you want to do though. definitely not the 421 cub

I had 34mm mikunis on a 421 cub and I went to 35 kehins and my mileage got quite a bit worse.

Definitely need to measure compression and/or take the head off and find out what size domes are in it. If the compression is high enough you could detonate and destroy pistons running just 93 octane.

Welcome back. I like riding my wifes YFZ450 in the trails, but my banshee is way more fun in the open dunes and hill climbs. I have an 04' limited, black on black, love it.

redline ported +4mm serval

Cam at Redline is not too far from Portland either (Sweet Home OR). You can get a special cool head style head with super domes. The super domes wont fit in a regular cool head. Or you can get the head that's on it re-cut.

I have a 421 cub with +4 swingarm 14/44 gearing and 21x12x8 10 paddle extremes. Last time I went to the dunes the sand was damp (Winchester Bay OR) which made it easy to get bogged down. Every once in a while I have too much traction when I'm on a steep hill climb in a low gear mostly because the power comes on so hard that the front wheels shoot for the sky, but just about right most of the time. I also have a pair of 21x12x8 9 paddle extremes that I now run on my YFZ450. They were a great tire too. Just a hair more wheel spin. Probably actually more duneable for playing around.

I believe your supposed to run .020" base gaskets with cub/serval cylinders, this would get your squish into the .040" range which is optimal. It shouldn't hurt to leave it the way it is though. On your race fuel comment, I also only go to the dunes a couple times a year, so the added cost of race fuel isn't that big of a deal. I'd be tempted to just leave it the way it is if you like the way it runs, but higher compression domes with a better squish probably would be a good seat of the pants improvement.

I think you could get a little better performance from a new set of 24cc domes with a slightly tighter squish, but its probably not worth the trouble. If you went to higher compression domes you will get more torque and probably better rideability, but again, might not be worth the extra expense of race fuel. I have a 421 cub but I am ported seval envious. I would sacrifice some top end power for my engine to come on the pipe at 4.5K and run on pump fuel.

Are the carbs synchronized good?

Got the e-mail invoice. All is well.

Thanks for the reply.

If your in a dusty environment you'd probably be better off with a foam filter as I believe they filter out the small dust particles better than a K&N. You will definitely have to go slow through mud puddles because you'll get mud and water splashing on open pod filters. I think I would consider keeping the air box in your case.

I found a couple parts I needed on FAST's online store. I've never bought anything from FAST before. When I go to checkout, the system says that they will figure out shipping and send an e-mail for immediate payment. How long does it typically take to get the e-mail so you can complete the transaction? When you call their phone number the message says they're too busy to answer the phone. I'm not complaining about the wait time to receive the e-mail because its only been a few hours, just wondering if the process is going correctly.

Bad ass!

big bore domes are for 68mm bores. You just need a stroker dome. You typically cant find stroker domes off the shelf, you have to have a set custom made. You definitely want to know what thickness your cylinder base gasket is before you order your stroker domes as this will effect the squish tolerance.

In theory it should't be making a bunch more HP now because it had the same engine set up last year with 34 mm mikunis and went over 32 miles with fuel left in the tank. Now it has 35 mm PWK's and is dyno tuned, its running great, better than last year, but only made it about 25 miles on the same ride. One possibility was I was just one the gas a little more than last year, but it didn't seem like my riding was that much different.

So, over the years, the more mods to the banshee the more the fuel economy has gone down. Many moons ago when I had a +4mm stock ported cylinder engine with 34mm Mikunis, I went 60 miles of logging roads on one tank. Last year on my 421 cub with 34mm mikunis I could do a 32 mile round trip on logging roads with some gas left in the tank. This year I just got my whole engine rebuilt and dyno tuned with 35 mm Kehins. I only made it about 25 miles before I ran out of gas and had to be towed the last 7 miles back to the car. The bike is running great, I am having a hard time believing that I lost 25-35% fuel economy just by switching to 35mm PWK's. Doesn't seem possible. Anybody else have that experience with a cub motor on 35mm pwk's? I'm wondering if I should have gone with the 33 mm pwk's or would it make that much difference?

Thanks for the replies. Fireball looks kinda spendy

21 cc domes could be right on the edge for pump fuel, 22 cc would be a safe bet. You'll need custom cut stroker domes to accommodate the piston going +2 mm above the top of the cylinder. You'll want to use the correct thickness base gasket the domes are cut for, or you could put the cylinders on and measure the deck height and then order domes to get the most accurate squish. Otherwise the builder making the domes has to make the squish a little bigger to be safe. You should definitely get the cylinders ported for the +4 stroke if they aren't already. 27.5 or 30 pilot, adjust needle to the best seat of the pants feel, 360 mains should be rich enough depending on the porting. If you have a builder port the cylinders they should be able to give you jetting specs that are real close.

Can someone hook me up with a link or a company name where I can get some A-arms that are made to work with YFZ450 shocks? I read somewhere on this forum that they exist but I never found the company name that makes them. Im not here to debate whether this is the greatest shock set up. I have a black 04 limited banshee and I found some black 04' limited YFZ 450 shocks a long time ago. I've been running the shocks on the stock A-arms for a long time now which works for me since I'm almost 300lb and they are plenty stiff. I haven't been able to make them bottom out which the stockers were horrible at bottoming out. I just want to have the correct suspension geometry so I'm not prematurely wearing out joints or something (although I haven't had any problems yet).

I just had my motor built by Redline. Cam was great to work work with to figure out what you can do within your budget, although I went way over budget because my existing 4 mil crank and clutch were bad. I thought the money I spent on the actual labor to do all the work he did was a bargain and the cost of parts that I got through him was very reasonable. I would do the +4 crank and porting with some stroker domes, a billet clutch basket and new clutch with lockout. Keep in mind if he finds some things in the trans that need replacement it could be a few more $. I'd think you'd be looking at around $1600 which might leave just enough for shipping.

You need to get the cylinders ported for a +4 stroke, most likely the previous port work will not be a problem as long as the porting was fairly mild. When your ready to put the motor together, you'll want to put the cylinders on and measure the deck height, the amount that the pistons stick above the top of the cylinder, then call someone like Noss heads and they can cut some stroker domes for you. Typically, a shop wont want to cut stroker domes for you unless they know the deck height because different thickness cylinder base gaskets will change that measurement. You wont find stroker domes off the shelf.