Coincidence or Correlation???

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Legion

Active Member
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Sep 15, 2008
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Location
Mesa, AZ
Hey Guys,
Let me pick your brains for a minute. I jacked my bike up on carjack stands last week to remove the rear tire to repair a slow leak. Prior to going up the bike ran great...now it runs like s**t! It stalls and wont idle. :bang head: When I keep the rpm's at about 2k it sounds like its backfiring up through the carb. The rear right one specifically. Will having the bike angled like that cause these symptoms or is it just a coincidence? I was thinking of trying the peashooter method to clean the carbs but was not sure if it was something else entirely.
Thanks for all your help.
 
If you tipped the bike foward a lot some crap from the bottom of the tank may have gotten drawn into lthe filter and/or carbs. Just something to check on.
Lew
 
Where exactly did you position the car jack(s)?

The stands were directly infront of the pipes on the frame. Once the back wheel was in position, the bottom of it was approx. 4in off the ground.
 
The stands were directly infront of the pipes on the frame. Once the back wheel was in position, the bottom of it was approx. 4in off the ground.
There are some wires down there, some from pickup coil/s. Check that they're ok.
They may been damaged with jack.

Did you touch the rear wheel only?
 
There are some wires down there, some from pickup coil/s. Check that they're ok.
They may been damaged with jack.

Did you touch the rear wheel only?


I never saw any wires on the frame in that area, I will have to look closer on Monday. The only other thing I did was tighten 2 bolts for the pipes. I get this annoying high pitched vibration sound as I downshift from 3 to 2 from around the can.
 
I'm going to agree with others, try the shotgun. I've never done it myself, thankfully never needed to, but I'm sure that it'll clear your carbs up. Sounds like they're gummed up. If you want, I can come up and have a look at it sometime.
 
I'm in agreement with them all :biglaugh:. If you didn't nick or pinch your pickup wires, chances are you may have freed up some junk while moving your ride around.
 
Thanks alot guys, I'll try cleaning out the carbs on Monday and see if that fixes the problem...hopefully. As I dont own an air compressor all I can do is the "Paul's peashooter method" (see link below). I'll give you all an update on Monady and let you know. Many thanks again. You all kick ass!

http://home.comcast.net/~onlyone12/carbs1.htm
 
Ok, I did the peashooter cleaning method and adjusted the idle a bit. It sounds a little better and doesnt stall now but it is still backfiring up through the carbs. :confused2: It seems to be just the right sided carbs...fYI, the v-boost had been removed. When you look into the carbs you can see small explosions and puffs of white smoke. :ummm: Im hopefully going to link a video so you all can see because I got nothing and need your experience.

http://www.youtube.com/watch?v=-_pqCnWn3Kk
 
That sounds like a jetting issue. What size main jets are you using?
 
That sounds like a jetting issue. What size main jets are you using?


I hate to say this but I have no idea. The guys on the board here helped me determine that its a stage 7 kit, but beyond that I dont know. :ummm: Maybe I should have it dyno'd and rejetted, eh?
 
if ti was running well and all of a sudden not so much. i doubt its jetting. not saying it couldn't be better but sudden changes aren't typically jetting eh?
 
I hate to say this but I have no idea. The guys on the board here helped me determine that its a stage 7 kit, but beyond that I dont know. :ummm: Maybe I should have it dyno'd and rejetted, eh?

Whenever you have a few free hours, let me know. I can come up there and help you get it all figured out. Each jet should have the size inscribed on it.
:thumbs up:
 
mine does the same thing, a lot when its cold, but after i ride it for a while i still notice it every now and then at a stoplight. maybe once every 10 stops.

my bike is all stock but i brought it down from Kansas to Indiana, so im guessing it just needs a rejet.
 
IMO you have wrong time sparking. I bealive your tci loseing sync and firein in the wrong timing. As i've suspected it propably have something to do with pickup coil.
 
Sorry you're having trouble. But, that is one cool video...probably not one on this board (including me) that hasn't had that backfire condition to varying degrees. Seeing it actually happen on video is great.

Hope you get it worked out. I'll hang up and listen.
 
Thanks for the idea guys, sorry I haven`t responded earlier today but it was way busy. I had thought about the jets, especially as it relates geographic area. The bike came from the Chicago area and I was curious if perhaps that was at least part of the issue.

Satariel666...how specifically do you check and then if needed adjust the timing? This is sounding like its getting beyond my capabilities...I've had my hands in someones chest massaging their heart but auto/bike mechanics seem to evade me without serious thought. :bang head:

Kozy...I might take you up on that offer. I'm working thru Thursday but maybe we can get together Friday and take a look.

Anyways guys, not to sound like a parasite, but keep the ideas coming. I truly appreciate it. :punk:
 
If it had been running fine previously then it can't suddenly be a jetting size issue.
Blocked passage or spark issue perhaps.
Do the simple things first, clean or swap plug, check HT leads and then consider ripping into the carbs.

My 88 bike after getting it all back together ran like crap at first but just a simple fuel additive /cleaner ( like Seafoam for example) fixed it like magic before I though about getting dirty hands.
 
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