My 89 Banshee has started having a problem in the past month. It acts like the plug is fouling on the left cylinder. It spits and sputters like it's fouled then will stop and goes on back and forth for a while. I think it still does it when I'm riding it because it sometimes has good throttle response and other times doesn't. Every time it acts up I usually either check the plugs or replace them but it still doesn't help. I thought maybe the coil was bad or the one plug wire was bad, so I put the left wire on the right and the right wire on the left. It wasn't the wire or coil that was bad since it still only acted up on the left cylinder. I have new carbs on it so I doubt if they could be the problem except for I got regular caps instead of the TORS tops. I did however make it a continuous loop in the circuit so it would run and it has been fine ever since I did this back in June. I thought maybe it could be the reeds but I'm not sure. I wanted someone else's opinion before I decide to buy parts and then end up being the wrong ones. When I bought my Banshee from my friend he took it to some dealer not in the area and they said the reeds were bad, but they didn't take it apart to look at them to tell for sure. I don't know why it would run this long without any other major problems. Of course they said the reeds were the reason it wouldn't drive too. Not the case. The guy who had it before the friend I got it from ran it with no oil in tranny and number 1 and 4 drive gears were frozen or welded to the shaft. Simply pounded them off with large hammer and used Dremel to grind off roughness of gears and shaft and it works fine now. It had many other problems but that would take quite a while to write so I think this is enough. PLEASE HELP or at least give an informative opinion. Thanks.

------------------
Jeremiah Lucas

1989 Yamaha Banshee

 

Oh yeah one more question. What is the best type of reed for my Banshee. I've been wanting to get new ones that might boost performance but I'm not sure which ones are the best or that if Rad, Ram, and V Force Delta Valves are better than better reeds in stock reed cages. Also if the Valves are better are they really worth $200+ for them or would I be better off with spending $26-$70.

------------------
Jeremiah Lucas

1989 Yamaha Banshee

 

Do a compression test first. If you are running a stock head your compression should be around 120-125 psi. Also I have heard people say that the left oil seal is known to go bad on a Banshee. I dont know if this will cause what you described, but its something to keep in mind. You say you removed the TORS. When you did this, did you put the slide back in the carb the right way. The cutaway should face towards the back of the quad. Take out your reed cages and inspect the reeds. If there is a gap between the reed and the cage, then they need replaced. When choosing reeds, I too was interested in a new reed cage until I read some thing that Tony Doukas said. He dynoed all the reed cages and the stock reed cages with Boyesen Power Reeds, he found that the Stock cages with the Boyesens outperformed all the expensive cages. So just get the Boyesen Power reeds and stick with the stock cages. They only cost around $30, it was the best bang for your buck I ever got. Great throttle responce, improved power throughout the entire rev-range. Oh well enough of me rambling on. Hope my information helps, If I think of anything else, I'll post it.

------------------
Jayson Blough '99 Banshee, '97 Warrior, '96 Blaster Yes I like Yamaha

 

I though of something else. Check to see if your main jet has fallen out. I have heard of them vibrating loose and falling into the float bowl. This would cause your rich condition.

------------------
Jayson Blough '99 Banshee, '97 Warrior, '96 Blaster Yes I like Yamaha



[This message has been edited by jblough (edited 10-26-1999).]

 

I checked my compression tonight and the left cylinder had 92 PSI and the right cylinder had 90 PSI. When I got my Banshee back in March it had a whole new topend, crank, rods, etc. It had some major problems in the tranny, water pump seal bad and impeller fins gone. It had many other problems but that was it for the motor besides the carbs being trashed. My point is that for 2 years before I got the Banshee it was not ridden for the fact that the gears in the tranny were locked up so it couldn't drive in order to put any wear on the motor. I have put maybe 30 hours on it since March since I didn't really get to ride it until May. Could it be that Banshee motors wear out fast, not rebuilt right, or somthing else, I don't know. Please give any suggestions, this is eating at me.

------------------
Jeremiah Lucas

1989 Yamaha Banshee

 

90 pounds is a little lite, 120 is about the norm stock hard to say if this is your problem. Try swapping carbs to the other cylinder and see if the problem travels with it I highly doubt your reeds will cause this

 

I did forget to warm up the motor before I tested the compression. I think that will make a difference, but I don't know how much of a difference. Everybody thanks for replying. It took forever to get a reply under Performance Mods and Suspension and Tires whenever I had a question.

------------------
Jeremiah Lucas

1989 Yamaha Banshee

 

Pull it apart. It may very well be a broken reed. I just ran into that with a friends quad. Never seen it before, but it does happen.

I hope that when you checked the compression, you basically kicked like heck for about ten times before taking the reading. Light kicking won't do it, oh, and did you have the throttle wide open too?

You didn't do what I did once did you? Leave a rag in the airbox opening when cleaning the air filter, then forget to take it out? Hey, stop laughing!!!

 

I think I know what my problem is now. I remember when I got my new carbs that the needle on one of them had a small bend at the end of it. I think it was on the left one but I didn't think at the time that it would turn into a problem. I guess it did though. One more thing, I don't see how if nominal pressure readings for the Banshee's top end are between 120-125 PSI's then how come mine is 90 on left and 92 on right, yet doesn't leak down. I left the gauge on each one for a little over 6 minutes as the repair manual called for 6 minutes and neither cylinder's reading dropped. The book said that if it dropped more than a pound in one minute you deffinetly have a problem and that if in the course of 6 minutes only lost a pound then that was OK. I don't see how if it lacks 30 pounds pressure per cylinder then how can it hold pressure and not leak down.

------------------
Jeremiah Lucas

1989 Yamaha Banshee

 

If your clyinder has been ported your compression will be lower than stock because they raise your exhaust port given you less compression time.


99 Scrambler 500 00 TrailBoss 325 87 Banshee