Shee_screams

The guy I bought it off of didn't say it was a cub, but I think it's a cub, don't recall seeing any power valves. Approximately how much compression would those domes give me? Yes I believe it's the 68mm with a 4mil crank

Not sure on the brand of the compression tester that we used or how well the threads sealed up. Anyways buddy rebuilt his banshee this summer with a fresh bore, and in theory he figured that he should have around 160PSI and that gauge read 140PSI, so i don't believe its accurate (I wish I had a primary standard to calibrate it with lol). Anyways for the leak down test that would tell me if the plug was mangled from an air leak or detonation? I guess it's possible the guy I bought it from bullsh!tted me and the bike didn't have near 180PSI? Given I don't know what what domes are in it or if they're still good. what dome size should i be running on that set up? My elevation changes occasionally. Right now my home riding area is about 2100 feet mark, however my "Home Home" is in the mountains and the base elevation of 1700 feet ranging up to probably 7000 feet. Also hit up St.Anthony once a year or so, just not sure how much the atmospheric pressure at different elevations effects the engines compression. What do you mean by the crank is next to go? Is it taking a pretty big chance if the compression is that low even though the the top end doesn't look horrible? I don't want to wreck anything more but I also would like to get away with out a huge parts bill lol. Thanks all!

To start out,back in February I acquired my first Banshee,1994 421 cheetah (about time). Got it from a dude that seemed pretty mechanically inclined, said he bought as a trinity big bore and with the help of FAST made it in to a cheetah 421...I asked him the compression of the bike and he showed me that it was 180PSI (holy sh!t), and he said he ran premium pump gas. I was a little surprised at this, as research on this forum has concluded anything over 165PSI on premium pump is a bad thing, anyways knowing there are more things than just compression that will dictate octane needed I took his word on it (it ran great!). Fast forward to March 6th, took it out for its first real rip at the farm. There was still some snow on the ground so it was hard to tell the true power of the machine, but Holy sh!t, it ripped! and ran MINT! Anyways now for the interesting part... We get out riding today, or well Sunday, let the banshees warm up and go out for some track time. I ran the banshee for probably 30 min of messing a round on a ghetto MX-ish track, she ran mint and the power was great. So now we are hitting the open fields after with 5" of snow on them (riding rural Alberta). Anyways she had balls and killer power, but once i hit 5th gear power band it seemed to fall flat on its face (almost like a 4stroke rev limiter) and stutter(think it might be pre detonation), Anyways after some figuring and listing me and my buddy discovered that the spark plugs were loose, like wobbly loose, WTF... We tighten the buggers back down and started her up again, the sound of the engine falling apart was gone. Anyways I take off and the same thing keeps happening(in every gear), it keeps falling flat and making weird sounds when the power hits. Get her back to the shop and pull the plugs and it turns the ground electrode one one of the plugs is almost gone and the other plug fully intact, but the center electrode looks pitted. Throw the compression tester on back at home and attempted to get a psi reading. One cylinder was 120PSI and the other was aprox 110PSI. Pretty close together I guess ( the tester may be off), probably not a hole in the piston. Anyways buddy is getting a scope from work to check out the cylinders without taking off the heads to see if there is damage. So my plan is to get some octane booster or a bit of VP race gas and mix it with pump gas and try it out Easter weekend and see what happens... Any input on whats wrong, what to correct or experiences would be extremely appreciated! Would like to have a running banshee to take out during semester break to St. Anthony lol. BTW on a semi limited budget, in collage and working at the hmedepot atm. 1994 Banshee: Cheetah cylinders (stock from FAST) Hot rods 4mil crank Pro desisngs cool heads (no clue what domes) Trinity 2 into 1 Carb Trinity Pipes V force reeds (number 2 i think) Thanks! Seth (Don't know how to post photos of the spark plugs... will use the search in the morning)

Fair enough, trail tech it is.

Hmm, probably works good, just looking for something a little bit cheaper if possible.

Hey, just picked up a 94 cheetah 4mil a couple weeks back and I am looking to do a DC conversion. My question is which rectifier to go with(no I am not getting an expensive name brand)? The link below is the one I think may work... four wire, single phase... Or if anyone on the forum sells them let me know. http://www.ebay.com/itm/VOLTAGE-REGULATOR-RECTIFIER-HONDA-MOTORCYCLE-GY6-125CC-150CC-4-WIRE-4-PIN-/121636737909?hash=item1c521d5375:g:xwcAAOSwBahVQUp0&vxp=mtr