bebetekbanshee358 Posted February 18, 2013 Report Share Posted February 18, 2013 if u got to throw a crank at it dude.. just go 4 mill... they sell cyinders here all the time for around 500 bucks sllready ported for 4 mill. ull never go back... i think u should keep it too...i played around stock motor for 2 years.im very heavy at 260lbs and need motor to push/pull me down the dunes.. i went with a 4mill... wishin i went with a 10 mill supercub or somehting of that nature.. u get tired of stock banshees qwick Quote Link to comment Share on other sites More sharing options...
KozyHeat Posted February 18, 2013 Author Report Share Posted February 18, 2013 4mil you say? I would if I had pipes. There is a set of fmf's ? for $110 shipped in the buy/sell. I will keep it stock - Honestly i haven't ridden many atv's so its all new to me - A twin 350 2-stroke is probably above my head a little bit. I want to squeeze out the most power on the stock cylinders because its out of the machine right now ready for a rebuild again. Everyone was impressed with my Banshee when it was running - Why not improve the stock cylinder characteristics and do it again except this time it will run all day. Not going to sell it either. Definitely got to put it through its paces before I would feel comfortable selling it anyway. Glad it blew up on me and not after I sold it. Its really not a bad fix. Quote Link to comment Share on other sites More sharing options...
camatv Posted February 19, 2013 Report Share Posted February 19, 2013 what country do you live in?? and SEEE I TOLD YOU TO SPLIT THE WHOLE F'N MOTOR! no way an 87-89 case with the OEM crank would survive a new top end. even a piston to wall clearance debacle like you put back together.... yes weld the damn crankshaft... if a shop will rebuild it with rods well go ahead and do it. if the lower rod bearing exploded it probably trashed the big pin. if it did you cannot replace that on a oem crank. you either have to get new webbs OR buy a complete new crank assembly. i'd suggest a NEW hot rods oem stroke crank. you tried saving $$ and now you have a trashed motor with new trashed pistons in it... ye ha Quote Link to comment Share on other sites More sharing options...
KozyHeat Posted February 19, 2013 Author Report Share Posted February 19, 2013 what country do you live in?? and SEEE I TOLD YOU TO SPLIT THE WHOLE F'N MOTOR! no way an 87-89 case with the OEM crank would survive a new top end. even a piston to wall clearance debacle like you put back together.... yes weld the damn crankshaft... if a shop will rebuild it with rods well go ahead and do it. if the lower rod bearing exploded it probably trashed the big pin. if it did you cannot replace that on a oem crank. you either have to get new webbs OR buy a complete new crank assembly. i'd suggest a NEW hot rods oem stroke crank. you tried saving $$ and now you have a trashed motor with new trashed pistons in it... ye ha rebuild the motor. you can screw with all the external stuff all you want. its not going to run better.. yank it split it redo everything inside. then take the good motor, and fix everything on the outside. your comp is way to low.. You were totally right Camatv! My fault but I AM learning and having pleanty of fun. Vertically split cases are new to me and now that I realize they split within an hour I think I will do it more often. I only put new rings on the existing pistons but i was slightly mislead with re-ringing. I asked a shop about it and thought they knew how to measure correctly with a bore gauge and would take care of it. I called up a shop and they said they can weld the pins but "typically in a stock application they shouldn't rotate so I don't think your going to need it." Is the crank pin is part of the inner web then? No doubt my pin is bad on the one side then - The chunks of the washers and rollers are everywhere. I thought the kits came with new pins but that must be for the aftermarkets. E.g. a stock stroke Wiseco connecting rod kit would fit on a Stock Banshee crank but you don't use the pins in that application? it is supposed to be for an aftermarket wiseco stock crank? I may need a left hand inner web :\ News to me! Thank you for trying to help me in November Cama. Don't give up on me! Quote Link to comment Share on other sites More sharing options...
camatv Posted February 19, 2013 Report Share Posted February 19, 2013 the oem cranks you have to buy new rebuildable style inner webb's. to do an oem crank correctley takes some real skill. you have to have them phased absolutely DEAD ON> if its off by 2 degree's your timing will be all over the place and the bike will have issues.. back in the way back days you could buy IMS inner webbs and rebuild a stocker crank. in all reality. you can purchase a NEW oemstyle hotrods crank for about 350ish? probably less than the labor, rod kits, and rebuildable center sections you would need.. used to be the labor alone was in the 100-125ish range .. since i do my own cransk i can usually redo a stocker for pretty reasonable. plus i can take a bunch of junk ones apart and after specing a ton of parts get one together that meets OEM specs pretty well usually with just using new lower bearings and thrust washers etc. but this takes time and a lot of specialty tools some of which i actually built myself.. if your motor has porting or really anything over pipes. it needs the crank welded.. Quote Link to comment Share on other sites More sharing options...
KozyHeat Posted February 20, 2013 Author Report Share Posted February 20, 2013 Not much for webs out there. Plus then I still need bearings + lab seal + labor. Probably going to go with a new crank even though its the most expensive option but I will trust the components. I answered my own question about the transfer porting. This is what I call the lower transfer ports. You want to match the port to the case and the gasket. Making them larger than thecase or the gasket at the bottom will not help you, it will cause unwantedturbulence. Found the answer to my question in the Banshee Porting DIY - thread pdf page 16 https://workspaces.acrobat.com/?d=5eNaltKS9ZOTGrp0FI7cGA give it pleanty of time to load Quote Link to comment Share on other sites More sharing options...
KozyHeat Posted February 21, 2013 Author Report Share Posted February 21, 2013 Looks pretty crappy but I will get in there and clean it with some power tools. I tapered it to just under halfway down to the oiling holes. Interesting not having tried it before. Quote Link to comment Share on other sites More sharing options...
KozyHeat Posted February 21, 2013 Author Report Share Posted February 21, 2013 Oah yeah, first picture shows how I marked the cylinder but the marker went under the paper/bled through so I wiped it off and redid it. Also I left room before the transfer was matched all the way so that I can sand / cut like crazy to get this more smooth. Second and third photo is how I modded my file. Just a cheap set from Home Depot I got a long time ago. I need to cut the smooth tip off so its just one file. I could see having a whole set of files would be nice. This one is a little rough. Quote Link to comment Share on other sites More sharing options...
KozyHeat Posted February 26, 2013 Author Report Share Posted February 26, 2013 My pistons are going to be Namura ( cast ) 'high-compression' pistons. That term hurts to use... but anyway I had a stupid conservative squishband before. With these high-compression pistons are they going to sink more into the head giving me a nice squish less than ~.61mm? Do they move the piston pin or do they have a taller piston? I am trying to determine gearing as well. I have long dirt roads. Check it out. Tire setup in the rear is 18 x 10 x 10 How silly would it be to run 16/38 gearing? Would it be un-ridable and slow? I want top speed but that gearing sounds to be a little excessive and will not perform low end. I do however like to go out and do some pulls though, so maybe its alright. I hope to take off at an aggressive pace and specifically faster than Yamaha Warrior. Other than that - Its going okay on the rebuild so far. Don't know about you guys but for me it takes time. Quote Link to comment Share on other sites More sharing options...
KozyHeat Posted March 1, 2013 Author Report Share Posted March 1, 2013 So... I got some used cylinders. The previous owner ran really tight clearance on the ring gap. Am I measuring wrong? Still waiting on a Crankshaft. Quote Link to comment Share on other sites More sharing options...
KozyHeat Posted March 1, 2013 Author Report Share Posted March 1, 2013 T for top and b for bottom gap You need the bottom ring gapped larger... Bore and pistons look really nice though - going to fix the ring end gap finish Port matching the cases ( these new cylinders match really close) Get my crank new gaskets on the case and seals, crank bearings, seal it up well. pressure and vac test it ^most important step should be ready to rip yet again. Quote Link to comment Share on other sites More sharing options...
Starwriter Posted March 2, 2013 Report Share Posted March 2, 2013 Are you measuring the ring gap in mm or inches? Take another toke and assess the situation. Quote Link to comment Share on other sites More sharing options...
ClayAiken Posted March 2, 2013 Report Share Posted March 2, 2013 My pistons are going to be Namura ( cast ) 'high-compression' pistons. I would seriously not go that route unless you want to be doing this all over again. Just use forged and be done with it. Quote Link to comment Share on other sites More sharing options...
HolySheet Posted March 2, 2013 Report Share Posted March 2, 2013 I would seriously not go that route unless you want to be doing this all over again. Just use forged and be done with it. x2. Cast pistons are known for breaking and then you have a lot bigger problem. Pro Lites are the way to go. Quote Link to comment Share on other sites More sharing options...
KozyHeat Posted March 2, 2013 Author Report Share Posted March 2, 2013 I believe you all have seen many failures and I also found some broken skirts and pistons specifically with Namura. The stock pistons are cast, these are cheaper cast pistons from an island off of China's coast, Taiwan. Maybe I'm doing it wrong but look at these numbers below... there is FAR to many people who just throw some pistons in their Banshee and don't even take the time to dress the piston rings... Would it be fair to say that if I threw these in with a) Too small of gaps bottom ring gapped LESS than the top ring? it would blow up? Glad you asked. I had that written down incorrectly on my photo because I am an idiot. Are you measuring the ring gap in mm or inches? Take another toke and assess the situation. I am measuring in Inches. I just forgot a ZERO.. or two Right cylinder - top ring .008" / .203mm - bottom .007" / .178mm | Manual recommended - 0.012 - 0.018in Left cylinder - top ring .009" / .2286mm - bottom .0075" / .1905mm | Manual recommended 0.012 - 0.018in using the stats from the service manual or calculating it based on general guidelines Bore - 64.69mm / 2.54685" multiplied by a recommended .005" per inch it comes out to about .012" So my top rings are at .008" and .009" - That is smaller than .012" correct? I don't have that backwards do I? I am going to get another set of feeler gauges. Im running a stock cylinder setup, nothing aftermarket. A little more porting than I would have liked for my stock pipes. A pretty big exhaust and some eyebrows, and cleaned up the bump in the intake. Nothing done to the transfers. Hopefully I am just wrong though and have messed up gauges / being an idiot. On any bigger of a budget I would have gone with forged pistons, and a fresh bore on my cylinders. I couldn't do that this time. The pro-lites definitely held up to my crank wobbling around and spitting out needle bearings everywhere. Quote Link to comment Share on other sites More sharing options...
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