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grantevans713 last won the day on October 11 2020

grantevans713 had the most liked content!

About grantevans713

  • Birthday 07/13/1990

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  • Gender
  • Location
    North Dakota
  • Interests
    Women, Guns and anything that goes fast

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  • My Banshee (optional)
    397 Dune port and 421 assassin

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  1. 120psi on both cylinders, you asked for squish clearance so I'll just tell you about my domes. Bore size 68.5mm (dome larger then the piston to cover variances) Step .038" squish band width 9.5mm squish band angle is 10 degrees ( 1 degree divergent angle) 24cc flat plate. Cap is solid but I have some others I can try. It only spits when it's overheating, I have been unable to add fluid until I get back to camp, so I've tried not getting it spitting hot. I added the excess coolant to top it off because it runs hot, and of my 3 banshees it's the only one having issues and the others are fine topped off. Temp guage is on hose coming out front of the case to the bottom of the radiator, it is tested and works properly. I have not tried adjusting timing but I left it where the guy who did dynotuning had it.
  2. I have a billet impeller. I know if I change domes it will open up the squish clearance and lower combustion temps, but I wanted to run pump gas. The mix rate is above and is standard for banshees. The radiator is good, no air bubbles, the guage is right and I know it is overheating because it's spitting out antifreeze. I do have an aftermarket fullbore plastic and custom grill with more space to let air in, as well as an air scoop. I think what I've decided to do is to run a second radiator under the seat. I can mount it low enough to get air, the extra coolant and space for airflow should cool the temps down. If that doesn't work I'll have to switch to 110 and 20cc domes
  3. So I checked a few other posts but the recommendations won't quite help my unique situation. So I'll start by listing my bikes build. It's a 421 with driveline cylinders, 68mm bore, long rod 4mil stroke, 24cc domes running 91pump, mikuni tm38s, shearer small bore in frames, oversized radiator, +6 timing. I have my jetting spot on, I even just got a dynotune done by Nate at KAN powersports, it's pushing 98hp and 51ft lbs of torque. I did play with the netting a bit after the Dyno, but I've chopped my plugs and it's right where it needs to be, if not a little fat on the mains from trying to keep my temps down. I have opened my case and checked to make sure my impeller is functioning properly. I have a MacDaddy inline cooler and tempguage, I am consistently overheating. I can't ride 10minutes WOT in a bowl without getting to 250 and stopping. About 20minites riding around the dunes without going above 3/4 throttle and I'm up to 230. Im running amsoil dominator, 20oz per 5gallon, 91 pump ethanol free from its own handle so no starter trash gas. I am running engine ice in the oversized radiator. So I am overheating a lot. Anyone have ideas? I can probably get some new domes for more squish clearance, would probably lower combustion temps. I could run more inline coolers but that seems redundant and like it wouldn't do enough. Im running an OEM frame, has anyone setup a radiator fan that works somehow? Doesn't seem like much space, maybe smaller ones? Is there anything else someone has done? I really don't want to ditch the pipes and carbs for something else.
  4. So I've been looking for similar builds but jetting has varies drastically with small changes. I'm planning on the first ride for these bikes to be sea level on the Oregon coast, both motors are fresh builds, new carbs, cranks, cylinders, heads, pistons, domes, etc. First bike: Toomy T5s 28pwk 6in K&N pods 4mil crank 66mm bore w/ aggressive trail port +3 timing 24cc domes chariot intake with boysean reeds I threw 160s in this, haven't even broken motor in as I haven't had time. What should I be around? I have 3 bikes I'll be making adjustments to when I get there, not trying to spend a ton of time pulling carbs and jets. Second bike 4mill crank 68mm bore with dune port Shearer inframes T38s 12in k&n pods +6 timing 24cc domes chariot intake with boysean reeds No idea where to start on this bike. Maybe like 350? Both bikes running 91pump gas and chariot heads. 3rd bike just got a refresh on top end, I was riding 290 at 5k elevation so I'm starting at 340. All help is appreciated!
  5. So I've had a busy winter with work and very few days off. Dropped one of my banshees off at a buddies for an overhaul. Got a bore done on cylinders, new pistons, carbs rebuilt, new cylinder head, domes, etc. Well he set it up for a long rod with cut domes because it's a 4mil crank, except it's a short rod 4mil. Today he got it going and took it for a test ride. It died halfway through third. Kicker won't move. How much damage should I expect inside the case? Just a new crank? Pistons probably shot? The case seems fine, he says there was no pop or crunch, it just revved then puttered out. Before he mentioned the kicker not moving, I thought maybe electrical. Any ideas what may have happened? What damage should I be expecting? How fucked is it?
  6. I have had a lot of bad luck with motor city. Bought a flywheel listed as "the pictured item" on ebay, even though it had 13 available. Showed up a little rusty with a rattle inside. Started a return, they said they could send me another with no rattle if I was fine with a lot of rust. Got a full refund at least. I inquired about an expensive used stator they had, asked if it was OEM and it was aftermarket. Used after market at OEM prices... They also sell new aftermarket ones for 1/5th the price. I have seen what I thought was deals on new parts that show up used. They have tons of stuff that look like deals, but I've never once been happy with a purchase and stopped buying from them.
  7. File a police report to start. Look for the bike or parts on it for sale used on local craigslist. Watch ebay within 100miles for the parts that were on it.
  8. Pick up the banshee, it's got $$$ into it and they are only increasing in price.
  9. 10½ years I'd clean your carbs while they are off to check the reeds.
  10. Change your oil every season. Always run premix. Tighten everything up after each trip so it doesn't fall apart. Check your plugs to make sure your jetting is right. Never go fast over a hill if you haven't been on the other side. Wear a helmet.
  11. If you replaced OEM stators and flywheels, I hope you replaced with more OEM. The cheap stuff could be causing a new problem.
  12. For every 2k elevation higher, you go down a jet size.
  13. I have a 397 4mil I run on pump gas with 21cc domes at 1800ft elevation. I have Mikuni t34s and I'm running 280mains, can't remember my pilots. Not sure if this helps. It would seem like if you're running pump gas your jetting is would change.
  14. Elevation is like 4800 and the big dunes in the back are like 500ft+. When I bought my bikes I considered that I mostly tide the dunes in St.Anthony, I'll go out for a while week every month in the spring/Summer. At home I might locally maybe once or twice a year. Compression drops at higher elevation, so I set my domes up to work with 105 here and 91 out of a pump there. If you're at sea level, your compression could drop 20psi going to 5000ft. Maybe go up a size depending on where you are if you typically run pump gas.
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