94BANSHEE Posted March 27, 2012 Report Share Posted March 27, 2012 Hi guys, I dont have too many mods on my banshee, V-force cgaes/reeds T-5 pipes cylinders bored .20 over Soon to have Chariot cool head with 21cc domes and the rest is all stock. Stock carbs, airbox (I wanna keep the airbox considering I drive in a lot of dusty and dirty trails at times) bottom end is completely stock with only the clutch that has been change to a Barnett I will be getting a see-thru clutch case as I heard they are built a bit tougher than stock I dont want to tear apart my bottom end coz it runs just fine. But Im thinking on replacing the jugs to maybe a serval cub. Id like to run the maximun, or closest to maximum, top end kit that I can with a stock bottom end and that is somewhat reliable. I dont ride in dunes or drag, but I do a lot of long trail/dirt road/ riding where Im in 5-6 gear a lot and would like to see some more top end Would the 393cc serval cub be the best or something else? Thanks!!! Quote Link to comment Share on other sites More sharing options...
Surfrjag Posted March 27, 2012 Report Share Posted March 27, 2012 No need for a see through cover really.. just get your cylinders ported Quote Link to comment Share on other sites More sharing options...
94BANSHEE Posted March 27, 2012 Author Report Share Posted March 27, 2012 Yeah..more of an apperance thing as well haha How much would porting run? Shipping from Canada to U.S and back isnt so cheap. If I did buy a top end kit..which one be the largest youd go with a stock crank untouched? I want something to drop in and go. No welding or opening everything. Just the top end Quote Link to comment Share on other sites More sharing options...
Infamous039 Posted March 27, 2012 Report Share Posted March 27, 2012 Just get your cylinders ported, shipping from Canada is not that expensive at all. I ship people parts to Canada all the time. I think you will be more satisfied with some ported cylinders over a stoke stroke Serval and you will save yourself tons of cash for same power output. Yeah..more of an apperance thing as well haha How much would porting run? Shipping from Canada to U.S and back isnt so cheap. If I did buy a top end kit..which one be the largest youd go with a stock crank untouched? I want something to drop in and go. No welding or opening everything. Just the top end Quote Link to comment Share on other sites More sharing options...
spurdy Posted March 27, 2012 Report Share Posted March 27, 2012 Yeah..more of an apperance thing as well haha How much would porting run? Shipping from Canada to U.S and back isnt so cheap. If I did buy a top end kit..which one be the largest youd go with a stock crank untouched? I want something to drop in and go. No welding or opening everything. Just the top end This isn't a 4 stroke. You don't increase the bore size of a stock cylinder to increase displacement for more power. The size of a stock cylinder is 64mm bore. You can buy pistons up to 66.5mm. I would never run that large of a piston just because they aren't that reliable, IMO. 66mm is as large as I would go. Now, the only time to over bore is to clean up your cyls, correct for taper or oblong bore which will happen over time. This is the life of your cylinders. Once you reach what you decide is maximum, you need to buy new cyls or resleeve your old ones. The amount of increased displacement is so minimal you wont be able to tell by riding it. Increased performance comes from better flow and different port timings. This is what gets changed with porting your cylinders. port durations are adjusted, casting flaws are removed, intake and exaust ports are reshaped etc. This is where the real power comes from along with componants to compliment the port job like carbs, exhaust, reeds, etc. A good port job will run anywhere from $350 and up depending on how extensive and who does it as well as if it needs a new top end at the time. Personally, I wouldn't run with a good port job on an unwelded crank. A good inexpensive way to make it run more effecient and make more power is to increase the timing with an adjustable timing plate. About $26 on ebay and easy to install. Again, I wouldn't get to crazy with timing without a welded crank. If a crank seperates or comes out of phase it can cause some expensive damage. Splitting the cases and sprucing up the bottom end isn't as hard as you may think. My 12 year old can put his bottom end together after watching me do it. Good luck. SP Quote Link to comment Share on other sites More sharing options...
BelleauCarl Posted March 27, 2012 Report Share Posted March 27, 2012 A have pull my jugs and crank, packed well and ship to hjr, im from quebec canada. Its not expensive you just have to be patient. For two jugs only it should cost around 40 with usps. And take 7 to 10 day for the ride By the same time builders got great price for topend rebuilt with piston. Quote Link to comment Share on other sites More sharing options...
94BANSHEE Posted March 27, 2012 Author Report Share Posted March 27, 2012 This isn't a 4 stroke. You don't increase the bore size of a stock cylinder to increase displacement for more power. The size of a stock cylinder is 64mm bore. You can buy pistons up to 66.5mm. I would never run that large of a piston just because they aren't that reliable, IMO. 66mm is as large as I would go. Now, the only time to over bore is to clean up your cyls, correct for taper or oblong bore which will happen over time. This is the life of your cylinders. Once you reach what you decide is maximum, you need to buy new cyls or resleeve your old ones. The amount of increased displacement is so minimal you wont be able to tell by riding it. Increased performance comes from better flow and different port timings. This is what gets changed with porting your cylinders. port durations are adjusted, casting flaws are removed, intake and exaust ports are reshaped etc. This is where the real power comes from along with componants to compliment the port job like carbs, exhaust, reeds, etc. A good port job will run anywhere from $350 and up depending on how extensive and who does it as well as if it needs a new top end at the time. Personally, I wouldn't run with a good port job on an unwelded crank. A good inexpensive way to make it run more effecient and make more power is to increase the timing with an adjustable timing plate. About $26 on ebay and easy to install. Again, I wouldn't get to crazy with timing without a welded crank. If a crank seperates or comes out of phase it can cause some expensive damage. Splitting the cases and sprucing up the bottom end isn't as hard as you may think. My 12 year old can put his bottom end together after watching me do it. Good luck. SP Thanks a lot for the advice guys! @ spurdy..I do have a timing plate. I never installed it yet. Also so you say to be careful with an unwelded crank. So what would be the maximum I could go regarding power and reliabilty while leaving the stock crank untouched? Quote Link to comment Share on other sites More sharing options...
spurdy Posted March 28, 2012 Report Share Posted March 28, 2012 Thanks a lot for the advice guys! @ spurdy..I do have a timing plate. I never installed it yet. Also so you say to be careful with an unwelded crank. So what would be the maximum I could go regarding power and reliabilty while leaving the stock crank untouched? When you advnace the timing, you are sending the ignition signal to the coil before the piston reaches top dead center. This initiates the combustion of the compressed air fuel charge early to obtain maximum thrust downward from the combustion cylce as soon as the piston passes TDC. With the advance set at zero, the piston has rolled through TDC and is already under some downward momentum when the combustion reaches full potential. If you change to race fuel or alky, they bun slower so you can start the ignition cycle even earlier to obtain a similar combustion. Advancing too much will result in the cuombustion reaching it's thrust downward before TDC which is known as detonation and obviously isn't good. As you can see, by advancing the timingyou place more stress the connecting components of the crank assembly. This can cause them to start to slip out of phase or even spread over time. This is the reason the cranks are welded together as we build higher HP engines. That being said, any unwelded, non keyed crank has the potential to slip. The more HP the motor can generate, the harder it performs, etc the greater the risk becomes. I would never have to make a call on how much timing to run on an unwelded crank because I would never use an unwelded crank. Just peace of mind for me. I would say you would be ok at 2 degrees of advance, maybe even 3 degrees. But there is no certainty to be had here. We know that cranks can slip but we never know how much we can stress them before they do. SP Quote Link to comment Share on other sites More sharing options...
94BANSHEE Posted March 28, 2012 Author Report Share Posted March 28, 2012 Thanks for the great insight and info! since my crank isnt welded...would running 2 degrees advanced timing plus a port job be fairly more powerful yet somewhat reliable? My cylinders are .20 over so since Im ready for new pistons should I also go up a notch on the bore, or is a bore only a last resort where there is damage? I also would be running T5s and cool head Thanks!!!! Quote Link to comment Share on other sites More sharing options...
spurdy Posted March 28, 2012 Report Share Posted March 28, 2012 Thanks for the great insight and info! since my crank isnt welded...would running 2 degrees advanced timing plus a port job be fairly more powerful yet somewhat reliable? My cylinders are .20 over so since Im ready for new pistons should I also go up a notch on the bore, or is a bore only a last resort where there is damage? I also would be running T5s and cool head Thanks!!!! Only bore if your cylinders require it. You can measure your cyclinders if you have a bore gauge to see where they are at and decide from there. Be sure to measure in at least 3 spots (top, middle and bottom) and in the x and y axis. Clymers has the acceptable limits. I wouldn't run a ported motor without a welded crank. Some may say you will be fine and you might not have any issues. Even a welded crank can fail but your level of risk goes down with a welded crank. Your level of risk goes up with more power and an unwelded crank. I'm not gonna commit to anymore than that. Lol! SP Quote Link to comment Share on other sites More sharing options...
slothman Posted March 28, 2012 Report Share Posted March 28, 2012 Only bore if your cylinders require it. You can measure your cyclinders if you have a bore gauge to see where they are at and decide from there. Be sure to measure in at least 3 spots (top, middle and bottom) and in the x and y axis. Clymers has the acceptable limits. I wouldn't run a ported motor without a welded crank. Some may say you will be fine and you might not have any issues. Even a welded crank can fail but your level of risk goes down with a welded crank. Your level of risk goes up with more power and an unwelded crank. I'm not gonna commit to anymore than that. Lol! SP Noob question: instead of welding the crank, would it be wiser to buy a stronger aftermarket high HP crank? How much power is the STOCK crank good for, if it is welded ? Quote Link to comment Share on other sites More sharing options...
cline Posted March 28, 2012 Report Share Posted March 28, 2012 Thanks for the great insight and info! since my crank isnt welded...would running 2 degrees advanced timing plus a port job be fairly more powerful yet somewhat reliable? My cylinders are .20 over so since Im ready for new pistons should I also go up a notch on the bore, or is a bore only a last resort where there is damage? I also would be running T5s and cool head Thanks!!!! Spurdy has really broken it down for you yet you continue to ask him about seeing how far you can push the limits of reliability. He is doing you a favor and you even thanked him for the insight and info but is it really sinking in? He is trying to save you from absolute catastrophe but you continue to ask, well what if I do this, what if I do that? Basically he is saying that on average from a site sponsor it costs $65 to true and weld a crank. $65 compared to a new motor = priceless. Here is a thread that was started today, mabey you should read through it. Information you should take from it is, Rod broke (crank failure), head might be fucked, cases top and bottom have holes and are ruined. What do you think? Wanna keep pushing the limit and chance your motor or spend $65. http://bansheehq.com/forums/index.php?showtopic=153502 Quote Link to comment Share on other sites More sharing options...
slothman Posted March 28, 2012 Report Share Posted March 28, 2012 Spurdy has really broken it down for you yet you continue to ask him about seeing how far you can push the limits of reliability. He is doing you a favor and you even thanked him for the insight and info but is it really sinking in? He is trying to save you from absolute catastrophe but you continue to ask, well what if I do this, what if I do that? Basically he is saying that on average from a site sponsor it costs $65 to true and weld a crank. $65 compared to a new motor = priceless. Here is a thread that was started today, mabey you should read through it. Information you should take from it is, Rod broke (crank failure), head might be fucked, cases top and bottom have holes and are ruined. What do you think? Wanna keep pushing the limit and chance your motor or spend $65. http://bansheehq.com/forums/index.php?showtopic=153502 Sorry to interupt .... But right now my jugs are off and are getting bored....how hard would it be to pull the crank real quick, and have it welded ? Yes I do have the service manual lol ... Quote Link to comment Share on other sites More sharing options...
sheerider11 Posted March 28, 2012 Report Share Posted March 28, 2012 Sorry to interupt .... But right now my jugs are off and are getting bored....how hard would it be to pull the crank real quick, and have it welded ? Yes I do have the service manual lol ... not hard at all. Follow there manual, your more then halfway there. And I don't trust un welded cranks. You have more then enough info on what to do. If this is all to save money then sell the banshee. Your just losing money trying to save money. Quote Link to comment Share on other sites More sharing options...
Coupelx Posted March 28, 2012 Report Share Posted March 28, 2012 Sorry to interupt .... But right now my jugs are off and are getting bored....how hard would it be to pull the crank real quick, and have it welded ? Yes I do have the service manual lol ... fairly easy if you take your time. after you do it a couple times its like second nature. i ran a stock unwelded crank for a year because i ran out of time last spring and needed the bike together, i trued it and threw it in on a dune ported stock cylinder. when i pulled it back out this winter it was a few thousands off on the PTO side webbing from crank twist. if it gets bad enough it WILL tear shit up and a failed bearing will kill a top end. Quote Link to comment Share on other sites More sharing options...
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