05.Banshee.SE Posted January 19, 2009 Report Posted January 19, 2009 Okay...here's a chance to tell me what direction you would go with this bike, if it was yours. 2005 Yamaha Banshee Special Edition -Pro Design Coolhead w/ 21cc domes -K&N Pods w/ Outerwears -Toomey T5s -Ported Stocker Cages w/ Carbon Fiber Petals -Razr 2s, YFZ450 Stocker fronts. -Jetting -Small things (TORS removal, parking brake delete, etc.) -Stock suspension all around. Here's what I want: more power, and more top end. I want to be able to rip other modded bikes apart in a straight line (more than I can now...I want insane power), but still be able to play around in the trails. My compression is low, so it's getting rebuilt, keep that in mind. I would rather have the power mods first, before I get into suspension shit. I run in a lot of beach sand because I live in Florida, and the trails are generally open and straight. There's a lot of dips/whoops, and a lot of open dune fields. The summer months here are wet as hell, so I'd like to be able to throw some Hoosiers on and drag it at the 1/8th mile asphalt for fun in the summer. I wouldn't mind running race fuel here because of the less consumption, and I can lower the domes for that time being. Here's what I was thinking: -Rebuild with 795s (I have not pulled it apart yet, so hopefully get away with a hone, resleeve, whatever) -4mil / 5mil crank, whichever is the longer one -Dune Port/Match Crank By Herr Jugz -Carbs, reccommended by Kevin -I would like to stay on pump fuel, so same 21 domes (cut.) [i'd like to get this all done as close together as I can, kind of like "phase 1: motor"] Shortly after: -Clutch -+4 swingarm -+ A arms and Axle, shocks. Quote
Snopczynski Posted January 19, 2009 Report Posted January 19, 2009 Why would you need the domes cut? Why the new crank if you think it just needs a hone? Quote
05.Banshee.SE Posted January 19, 2009 Author Report Posted January 19, 2009 Why would you need the domes cut? Why the new crank if you think it just needs a hone? Stroker crank -> more power -> long rod = cut domes. (I saw what you were talking about, I made it more specific... 4 or 5 mil... the 4 mil crank that's longer, 115 I think? I don't know if that's considered a 5 mil or not.) Quote
dajogejr Posted January 19, 2009 Report Posted January 19, 2009 There are two different things you're talking about... A stroker crank moves the big end pin offset from the center further, give your piston a longer throw from the bottom to the top. For example, a 4 mil stroker crank has the crank pin off set 2mm further. 2 mm on the bottom and two on the top =4mm stroke. A long rod lessens the side angle on the pistons...in other words, your pistons are trying to be pushed out the side of the motor...when you use a longer rod, it lessens the angle, less stress, etc. When you get a stroker crank on stock cylinders, you can put a spacer plate on the bottom of the cylinders or get domes cut so the piston travels 2mm further up into the head. A stock banshee rod is 110mm. The most common long rod is 115mm for smaller stroker cranks (say...10mm or less). You buy a piston that has the wrist pin hole closer to the dome, or top of the piston. A long rod doesn't increase the size of the motor or really even create any HP, it just takes stress off the crank. Does this make sense? Quote
05.Banshee.SE Posted January 19, 2009 Author Report Posted January 19, 2009 I would imagine a) the long rod is better because of the less stress on the motor, and it's better to cut the domes instead of putting a spacer, and the spacer could create another a new place for an air leak? I think I actually heard that from you somewhere since I've been here. But then the long rod doesn't create power like the stroker does...? Why would someone want a long rod over a stroker? Sorry...this is why I never did any internal stuff like this, I just don't know it. Quote
278 Posted January 19, 2009 Report Posted January 19, 2009 As daj was saying... The reason for a long rod is simple, less stress. A stroker and long rod are 2 different things. Let me try to rephrase what he said and see if that helps. The stock banshee crank has a 110mm long piston rod. A 115mm long piston rod (5mil long rod) just puts less stress on the cylinder walls because your pistons are being pushed against them. A stroker crank makes your piston move up and down more. So a 4mil. would move the piston 2mm higher and 2mm lower because the ro journals on the crank are of set 2mm. So that 2mm up and 2mm down equals 4mm. 2+2=4 A long rod stroker crank such as the 4mil long rod (+4mil +5mil crank) moves the piston higher 2mm and lower 2mm because of the stroker, but it also has a longer rod. So it puts less stress on the cylinder walls. Does it make sense like that? Quote
dajogejr Posted January 19, 2009 Report Posted January 19, 2009 Whether you get a spacer plate or your domes cut, the cylinders need to be ported to match the new stroked crank. In my opinion, a long rod on a stock stroke isn't worth it unless you're running HUGE compression and/or Nitrous... Even then, lots of guys run the stock rod. There are a few that will tell you a short rod revs faster as well. Quote
05.Banshee.SE Posted January 20, 2009 Author Report Posted January 20, 2009 Ah, I get it now. So I can stroke it, long rod it, or do both. I see now that the long rod won't be necessary unless I'm running some really high stuff! Since I'm planning on 93 octane, and keeping my domes down to 21s, I will not get the long rod. The long rod stroker/long rod/stroker thing was confusing me. I didn't realize you could do both, and in what instances they should be used. You guys are great, thanks much for your patience and help. :beer: In summary: - Don't run the long rod because I'll be on 93 pump w/ 21 domes. - Can you tell me what compression "cut off point" the long rod would become necessary (if there is one)? - If I want to go to a "big bore," I'm better off with a Cheetah kit. - Is the longer rods what makes guys have "10 mils" or "14 mils"? (Stroker + Longer Rod) - Make sure my engine builder raises the exhaust/intake ports to accomodate the +4mms. (Does this change what port option I get at all? Dune/Drag/Trail) Quote
vulvafan537240 Posted January 20, 2009 Report Posted January 20, 2009 Ah, I get it now. So I can stroke it, long rod it, or do both. I see now that the long rod won't be necessary unless I'm running some really high stuff! Since I'm planning on 93 octane, and keeping my domes down to 21s, I will not get the long rod. The long rod stroker/long rod/stroker thing was confusing me. I didn't realize you could do both, and in what instances they should be used. You guys are great, thanks much for your patience and help. :beer: In summary: - Don't run the long rod because I'll be on 93 pump w/ 21 domes. - Can you tell me what compression "cut off point" the long rod would become necessary (if there is one)? - If I want to go to a "big bore," I'm better off with a Cheetah kit. - Is the longer rods what makes guys have "10 mils" or "14 mils"? (Stroker + Longer Rod) - Make sure my engine builder raises the exhaust/intake ports to accomodate the +4mms. (Does this change what port option I get at all? Dune/Drag/Trail) if you get a 4mill, get the long rod 4mill. less side load on the sleeves. you have to get 795 series pistons to accomadate for the long rod. you also need the stroker domes for the extra 2mm at tdc. a 10mill crank is a 10mm longer crank. 64mm instead of 54mm. and tell your builder that you want a 4mill dune port. :thumbsup: Quote
05.Banshee.SE Posted January 20, 2009 Author Report Posted January 20, 2009 A long rod stroker crank such as the 4mil long rod (+4mil +5mil crank) moves the piston higher 2mm and lower 2mm because of the stroker, but it also has a longer rod. So it puts less stress on the cylinder walls. Can this be run on the ported to match stock jugs with a Pro Design Head and domes? Does that mean I have to cut the domes more or something? If I run a 4mil, I have to cut it so it can go higher...and if you add in a longer rod, does it have to go even more? Or does is it strictly change the angle? EDIT- NVM, I see that the pistons accomadate the long rod. So the new pistons, plus the cutting means I can run the long rod and the stroker. Thanks. Quote
brian Posted January 20, 2009 Report Posted January 20, 2009 Call Kevin. He will explain all of this stuff to you and give you the best reccomendations for what works best with his port work. He is very patient and will take the time to help you understand whats going on. He will also have modded domes ready to go. You wont have to cut any yourself. Quote
05.Banshee.SE Posted January 20, 2009 Author Report Posted January 20, 2009 Yeah, I was looking at all the options on his site. Seems a lot easier just wait longer, and pay him to do it all lol... Anyone know the shipping cost of a motor? (Roughly $100 or something isn't it?) Quote
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