Mast372MIND

Open airbox w/ K&N needs a 290-300. Closed airbox you can run the 260. Do yourself a favor and go buy some more mains. I would just go ahead and buy 270s, 280s, 290s, 300s, 310s, and 320s to cover all riding temps. You will also need 27.5 and 30 pilots. 30s run better in cold weather (easier starting below 40 deg F). Run needle in 4th or 5th clip without reeds, and 3rd or 4th clip with aftermarket reeds, depending on if it is summer or winter weather conditions, respectively. I run 300s w/ 27.5 pilots at 70deg F (+/- 20degF) and 1200 ft. Mods are K&N, no lid, fattys, TC2s, and dual stage reeds.

I have just about the exact same mods as the OP: FMF fattys w/ turbine core 2 mod quad adaptor w/ K&N air box lid off boyesen dual stage power reeds My elevation is about 1200 ft. I've jetted my bike with just about every main/pilot/needle combo I could. I've tried 280, 290, 300, 310, 320, and 330 on the mains, 25, 27.5, and 30 on the pilots, and 3rd, 4th and 5th clip positions on the stock needle. For 60degF and above, I've found that 300 mains are the way to go. 30-60degF I run 310s and below 30degF I run 320s. The clip is best in the 4th position with the reeds and the fattys. For 50-60deg and below the 30 pilots help the bike start on 1st or 2nd kick when shes cold and no trouble when shes warm. When it gets above 60 or 70 degF, I run the 27.5 pilots and it starts fine when cold. So, as far as the pilots go, I think that the 30s are about spot on for me in cold weather. That being said, it does smoke quite a bit and will show some unburned premix on the exhaust tips until she gets warmed up. I really just think that FMF suggests 30s for easy starting. When I run 25 and 27.5 pilots in cold weather, it takes about 6-10 kicks to start her up cold. I honestly think that their jetting recommendations are just about spot in 60 deg F weather.

I'm no expert but if it was my shee, I would take the time to fix that problem correctly before riding it for long periods of time or in dusty conditions. I would not use silicone gasket on the balance tube boots. If the gasket material breaks down it would get sucked right into the cylinder. I'm suprised its not running lean on that side (if it is leaking air through it).

They are 320s.

I've only had the quad since November, but I think its been happening since I got it. I only say that because the carbs were very dirty around the bowls, suggesting that there was fuel/oil mix leaking slowly out and collecting dirt. Like I said, the leak is very slow (it doesn't drip or anything unless it is allowed to sit overnight or longer, even then only a few drops). I also noticed that if I let it idle for about 1 min with the fuel off before putting it up, it doesn't leak (obviously due to a lower bowl liquid level).

Thanks for the reply. I think I'll tear it down again after the weather warms back up in OK. I will pay attention to the things you mentioned when I go back through it and update the post with what I find out. If anyone else has anything else to add in the meantime, please do so. Thanks, Rob

Yeah, I shut off the fuel anytime she's not running.

Hey guys, I'm having a problem with my left carb leaking gas. It seems to be a very slow leak, so its not a problem when riding, but when I put it up for a few days there is an oily residue that forms around the bowl. Its only happening on the left side carb. I put a piece of paper under it and it only dripped once overnight, so its not that bad. However, i would like to get it fixed just to avoid pooling gas around the bottem end cases. After I looked at it this morning, I think there was a little reside above the bowl flange, so I dont know if its coming from the bowl or maybe a leak around the fuel line. Anyone else ever have this problem??? Thanks! -Rob

So, I went ahead and put them in. They fit well and the bike runs fine so far (only rode for a few minutes up and down the street). Thanks for all the replies!

So why do these jets have different engravings? Do you think that they are just an off-brand and the others I have are Mikuni?

Hey guys, Need help ASAP. I normally buy jets from jetsrus.com, but I wanted to get some 320s for rejetting today so I went to a Yamaha dealer. I have stock carbs and every size from 260-330, except for the 320s. So anyways, I go in and ask for some and he brings some out. They are the normal hex head jets and they have an identical hex head size and thread pattern to all of the other jets I have. Only difference is that the number is written on the side of the hex head rather than on the top like my others. Instead of just saying "320", they say "320RD" on the side. I also noticed that the beveling is different on the jet throat (viewing from top of hex head) than my others. All of the other jets I have use a larger (wider) bevel. However, the throat of the jet seems to be the right size (it is between the sizes of the 310s and 330s that I have). Are these jets just off brand? Are they okay to use? Will the different bevel make it perform different that the normal 320s? Let me know what you think. Thanks, Rob

Well, I wen't ahead and bought some 27.5 pilots today. Couldn't find them at any of the dealers or the shop I typically use. Ended up going to another shop out of town, which is a great place for banshee parts. Only problem is that they were $10 EACH and they look used!!! If thats not insane, I don't know what is. Double the price of the dealer AND ITS USED??? WTF??? Anyways, I went to install them and realized that I don't have a screwdriver long and skinny enough to access the pilots. Also, I decided to try the clip at the 4th position from the bottom rather than the 5th, due to all of the comments regarding it sounding kinda rich. Tomorrow I'm going tool hunting and will post again with the results. Thanks for all of the help!!!

Okay, I bumped up to 280 mains, ran it, bumped them up again to 290s -- much better plug color with the 290s, so I settled on that for the winter months (tuned at 35 deg F). Also went ahead and moved clip to 5th position from blunt end, 1st from needle tip -- this totally fixed the bog/hesitation problem at 1/2 throttle. Runs like a dream now. Pilots are still stock and air screws are 2 turns out. Plugs look good at idle, 1/2 throttle and full throttle. I had to adjust the TORS to get the carbs to sync right, which I hopefully performed correctly. Is there a way to tell if the carbs aren't sync'd properly by how it runs at idle, or must you just go by the little windows and the indicator mark with the throttle slide valve? Thanks for the advice!

i might go ahead and try the 280s, just to be on the safe side (plus its gotten a bit colder around here since last time I rode, dropped from 55 down to about 35 deg F). all the way rich would be the 5th clip position from the blunt end, right? I think I might try the 4th clip first, then move from there. Whats the easiest way to change the clip position? I still have the TORS setup on mine and I hate having to remove the gas tank just to get to them, but if it must be done than it must be done. Also, do the carbs need to be re-sync'd after moving the clip position? Thanks for the help guys... I appreciate it!

yeah, the pilots are the stock 25s and the air screws are 2 turns out.

yeah, the 270s seemed to be pretty good. I started to put in 280s as you suggested before, but the package on the reeds said that they tend to make it more rich so to go down 1 size on the mains, hence the 270s. as far as the bog, it happens right around half throttle. the motor builds power to about half throttle fine, then hesitates until it is opened up to about 3/4 then really takes off good and runs strong on out to full throttle. it revs fine under no load, if that makes any difference (doesn't help me ride any, haha).

************* UPDATE: Everything is good now... no more tubes rubing the frame. I played around trying to get it to line up good, but couldn't get any results. I ended up just pulling on the silencer a bit (gently, but with some effort) and tweeking the pipe where it was contacting the frame (well actually where it was contacting the rubber exhaust collar). After just a few tugs it had put a little more bend into the silencer tubes and I now have about 1/8-3/16" clearence. No creases in the pipe or anything like that, just slightly increased the bend angle. Thanks for the help.

Hey guys, Just finished installing some things I bought for my stock shee and I'm trying to get the jetting dialed in. FMF fattys w/ TC2s, boyesen dual stage power reeds, K+N with 6 vents in airbox (still has lid on it). Anyways, the bike is running great, except for one problem. It bogs right at about have throttle, so I'm thinking its a needle clip issue. It's running about 40-50 deg F on average here in OK and my elevation is about 1000'. I think that I have the mains set up about right at 270s, but I'm considering bumping up to 280s (as AKheathen suggested), but there are no real problems there is the plug color is good and tan. Anyways, given my mods do you think the clip should be typically moved to a leaner or richer position to solve my problem?

I think that a thermostat would only help if you had a radiator with a duty high enough that it could expel TOO MUCH heat. For instance, if your banshee had an aftermarket radiator that was bigger and/or more efficient, than it would benefit from a thermostat to keep it from running too cool by only circulating coolant when needed rather than at all times. I mean, it is obviously true that if you have a larger temperature difference between the coolant and the engine you can remove more heat per volume of coolant. It's also true that the radiator will relieve more heat if the coolant is hotter because it will have a larger temperature difference between the coolant and the air. Basic heat transfer equation: Q = h * A * (T_hot - T_cold) (steady-state), where h is a lumped heat transfer coefficient accounting for convective and conductive heat transfer, A is the heat transfer area, and Q is the heat transfer. So, if the coolant moved more slowly, you would have a more efficient heat transfer mechanism due to a larger temp difference. But, it is only more effective on the basis of the amount of heat removed per volume of coolant. When you approach the limitations of the radiator, the coolant must circulate as fast as possible to adequately remove heat. When you're bike is in an overheat condition, the coolant is entering the radiator at its hottest temperature, giving you the most effective heat transfer you can get from the radiator you have. In the case of a banshee at consistant high load conditions, the radiator still cannot evolve enough heat to cool the engine. It might help during some cases, but not if you're running the bike at high load for an extended period of time. Think of an R1... If the coolant system continually circulated than you would never be able to get the bike up to design operating temperature unless ambient temperatures were really high or the motor was operating under continual high load conditions. However, if you slap a YZ85 radiator on an R1... well, you get where I'm going. It would be nice to have some heat transfer calculations to back all of this up, but considering that I don't have dynamic simulator software (or time to do the calcs by hand or the specs needed for the study to be completed), I think that we should just assume a thermostat wouldn't resolve your cooling problems with a stock radiator. I'm a chemical engineer (not a mechanical engineer), so this type of problem doesn't fit into any software tools I have on hand at work. It would be interesting to see this if someone works at a place that would have such computing tools as to allow them to run the numbers.... Otherwise, I could do some psuedo-dynamic calculations in Excel if someone would give me the exchanger area of the radiator and the area of the engine cooling loop (approximations will work). As for the SVT lightning reference... The lightning doesn't operate at propetual high load, so it makes more sense to have a setup with a thermostat to promote more effective heat transfer during brief conditions of high load. I'm not an expert on radiator design, but thats my input. Just my $.02...

Elevation is right around 1200 feet and temp for the winter will be in the 45-60 deg F range...

Okay thanks. I will prob just keep those reeds I already bought for now because I really don't want to spend anymore money. I can always buy the reed cage later. Hmmm... I wonder if Chariot will sell me the cage without the reeds for a bit cheaper...? I will have to get with them on that. Given my mods and elevation, what do you think would be a good jetting setup? I was thinking somewhere around 270 or 280 mains, but am not sure. (I guess this question would be better asked in the jetting and exhaust forum, but no use in double posting).

Hey guys, I recently bought some Boyesen superstock carbon reeds to put in my stock reedcage for like $70. Then I got to thinking about just returning them and saving up for a full Chariot or VF3 cage and reed set. I guess my question is rather or not the superstock carbon reeds will even make a difference in a stock reed cage and how much of an improvement would it be to go ahead and step up from there to a VF3 or Chariot cage+reed set. Only mods to engine are ModQuad K&N w/ adapter plate and FMF fatty pipes w/ TC2 silencers. Also, is the FMF jet kit worth getting for $70? I know that it doesn't come with pilot jets, only three sets of mains and a needle... (I am at about 1000' elevation in Oklahoma). Or should I just buy indiviual jets and make my own kit? I don't plan to do any more mods to the engine other than the pipes and reeds. Thanks, Rob

Alright, I will have to try that when I get back home. I'll let you know how it turns out. Thanks, Rob

I had to go out of town for the week so I wanted a quick fix. What I ended up doing for a temporary fix was just cutting one of the two unused rubber exhaust collars in half and wedging it between the silencer tube and the frame. It's a tight fit so I don't think it will fall out before I get a chance to mess with it again. I figured it would provide mechanical and heat isolation between the frame and the silencer tube, plus you cant see it under the plastic! AKheathen -- Think that sounds alright??? Is that similar to what you had in mind when you were referring to with the heater hose??? Hell, if it holds up I might end up just leaving it. I still need to rejet the carbs, so thats the first thing on my list to do when I get back...

Haha, true, I like your attitude about it. Do you think it would be okay to just ride it. I just don't know if the heat might stress the frame??? In the install instructions it says that it should not be contacting the frame, so that's what's making me worry about it. I thought about just wrapping in it a shop rag and calling it a day, but that's just kind of a "southern engineering" fix to the problem.