Jump to content

Won't idle, zero bottom end power


Recommended Posts

My buddy has a '97 banshee with stock carbs, T5's, TORS delete, pro design adapter with K&N and stock cylinders with some porting.  Has 280 main jets and 25 pilots.  It has been running fine for the past 3 years or so and all of a sudden won't idle and just doesn't have any bottom end pull.  With it in neutral it won't rev out clean, but go put it in gear and ride it and it'll come up on the pipe clean as long as you hang it wide open with a load on it.  It also smokes excessively compared to mine and we both run the same 32-1 Yamalube R2 ratio.  It just seems like it's getting too much fuel. It also runs through a tank of gas about 4 times faster than my '95 which has the same basic mods except mine doesn't have any porting done.  He's had the carbs apart and cleaned several times and even swapped carbs, intakes and reeds with his other banshee and still has the same issue.  Just seems like it's flooding and only runs decent if it's under wide open throttle.  The plugs always come out fuel fouled where he hadn't had any problems with fouling previously.  Any ideas on what could be the issue here?  We ran a compression test and both cylinders show 105 psi.  Seems a bit low as mine showed 120 psi with the same tester, but would that cause these symptoms?

 

 

Link to comment
Share on other sites

Thanks for the reply.  I kinda figured it might be time for a new top end with that compression.  Elevation is ~1300 ft according to Google and we ride at LSOK, which is almost 1500 ft.  I have 290 mains in mine and was also surprised to see his only had 280's.  I'm just curious, if the jets were too small then it would be running lean, right?  The fuel fouling and excessive smoke and terrible fuel economy had me leaning toward too rich, but just didn't make sense considering his jetting.  He hasn't changed any jetting and it ran fine last year before he put it up for the winter.  This all started when he pulled it out of storage for our ride last month. 

Link to comment
Share on other sites

  • 3 weeks later...

Crank seal maybe, sence u checked everything eals out like carbs,reeds,intakes allready.

Or maybe it aint got strong enough spark to burn off the fuel. Dose one pipe smoke moe then the other?

Just throwin some ideas out there,

Let us know how it go's.

Edited by Yamahafan#1
Link to comment
Share on other sites

Thanks for the replies guys.  The slides are in the correct carbs.  We had them out a few times during the carb swap and made sure they went back in the correct carbs.  Crank seals was my first thought considering the amount of smoke, but his transmission oil is still full.  I thought if the crank seals go bad it would suck oil from the trans and smoke excessively, right?  This thing puts out a steady fog of smoke out of both silencers.  It's always smoked a bit more than my banshees, but this is like he mixed 50/50 gas and oil.  I even topped mine off out of his gas can without issue so I don't believe his premix ratio is the problem.  It just seems like it's getting way too much fuel all the time.  Runs great when under wide open throttle, but otherwise just bogs and goes through fuel like it's just dumping straight into the cylinders.

 

He's decided to stop messing with it and is going to drop it off at FAST to have them diagnose and rebuild it.  I was hoping we could dig in and find the problem ourselves but his schedule and motivation to work on it just aren't cooperating.  Best to let a pro figure it out for him. 

 

Thanks to everyone that's offered advice. 

Link to comment
Share on other sites

Thanks for the replies guys.  The slides are in the correct carbs.  We had them out a few times during the carb swap and made sure they went back in the correct carbs.  Crank seals was my first thought considering the amount of smoke, but his transmission oil is still full.  I thought if the crank seals go bad it would suck oil from the trans and smoke excessively, right?  This thing puts out a steady fog of smoke out of both silencers.  It's always smoked a bit more than my banshees, but this is like he mixed 50/50 gas and oil.  I even topped mine off out of his gas can without issue so I don't believe his premix ratio is the problem.  It just seems like it's getting way too much fuel all the time.  Runs great when under wide open throttle, but otherwise just bogs and goes through fuel like it's just dumping straight into the cylinders.

 

He's decided to stop messing with it and is going to drop it off at FAST to have them diagnose and rebuild it.  I was hoping we could dig in and find the problem ourselves but his schedule and motivation to work on it just aren't cooperating.  Best to let a pro figure it out for him. 

 

Thanks to everyone that's offered advice. 

 

Ok, thats what I thought about mine too when I got it, I always kept it as it was, but mine was wrong and they were backwards.. The angled part goes away from the motor. Mine acted exactly like yours, and I thought the same way. So just making sure because I beat my head against a wall for weeks until I really looked at how they were.  :)

Link to comment
Share on other sites

Ok, thats what I thought about mine too when I got it, I always kept it as it was, but mine was wrong and they were backwards.. The angled part goes away from the motor. Mine acted exactly like yours, and I thought the same way. So just making sure because I beat my head against a wall for weeks until I really looked at how they were.   :)

 

 

Thanks for the suggestion.  I suppose it's possible he swapped them around and we just never noticed the next 4 or 5 times we had the carbs off.  He always pulls the carbs and cleans them at the end of the riding season before he puts it up for the winter.  Would make sense since these problems just started and it was running fine last year.    I'll run it past him.  At least that would be a quick and easy thing to check.

 

Thanks again everybody.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
×
×
  • Create New...