Help wanted with carbs on xv1100 1991

[Theantidote]

Hei there...
my new bike seems to have a dual carb issue and would really like to learn how to nurse her back to health...are there any people who would be willing to help by guiding me through the process??? I'm capable of basic mechanical stuff but pulling this thing down blind kinda freaks me out...
if you can help and are out south akl way (exit 461 - Drury) please let me know...winters coming so i guess nows a good time...

cheers

[Theantidote]

i thort i better reply to my own thread...hmmm...perhaps i need to offer some beers/coffee and a hot meal to get some help...hmmm soo coffee and a hot meal is offered to the very clever person that can help me with this...

[cmoore]

Hi, what sort of help are you after...i have worked on these carbs and have a few good parts suppliers and links to sites etc, also have carb giudes for doing the work, pm me and give me your email and i will send you what i have.

[nzspokes]

Give a description of what is wrong. Most carbs are simple to work on. Get the base settings the same. Just strip the carbs down according to the manual if you have one. Take a read through this if it still has issues. I have carb sync gear if thats needed.

http://www.factorypro.com/tech_tunin...m_engines.html

But first tell us what is wrong.

[Theantidote]

Hi, what sort of help are you after...i have worked on these carbs and have a few good parts suppliers and links to sites etc, also have carb giudes for doing the work, pm me and give me your email and i will send you what i have.

Great to hear from you...really just the usual viagra probs....rear cylinder back firing and running rich (possibly richer than necessary) whilst the front seem a bit lean (both checked by checking the plugs). I've done single cylinder carby stuff before so know the basics but the viagra seems a bit more complicated...
so the help i need is someone who knows more than me to come over if poss and just guide me through it...i may even need to pull the bowls off to give em a clean...i don't think they have had much attention since long before i got her...
i haven't found a youtube that leaves me with the confidence to attack this...am regularly checking out viragotech but same deal...so that's what i'm looking for...i'd love to learn how to do this so i can pass some extra knowledge to my 10 year old boy also...
cheers

[Theantidote]

Give a description of what is wrong. Most carbs are simple to work on. Get the base settings the same. Just strip the carbs down according to the manual if you have one. Take a read through this if it still has issues. I have carb sync gear if thats needed.

But first tell us what is wrong.

Ohhhh hi man thanks for the reply
see above for what i'm moaning about...had a look at the link you sent...thanks for that...but again not so confident to pull my baby to bits on my todd...i like her too much for that kinda thing...

thanks again for the riding tips the other night...i haven't had a chance to get out since, next fine day maybe...

[nzspokes]

Great to hear from you...really just the usual viagra probs....rear cylinder back firing and running rich (possibly richer than necessary) whilst the front seem a bit lean (both checked by checking the plugs). I've done single cylinder carby stuff before so know the basics but the viagra seems a bit more complicated...
so the help i need is someone who knows more than me to come over if poss and just guide me through it...i may even need to pull the bowls off to give em a clean...i don't think they have had much attention since long before i got her...
i haven't found a youtube that leaves me with the confidence to attack this...am regularly checking out viragotech but same deal...so that's what i'm looking for...i'd love to learn how to do this so i can pass some extra knowledge to my 10 year old boy also...
cheers

Ok sounds like its dumping fuel into the pipe, so back fire. I would replace the plug first to eliminate that then take a look at float height and the float valve.

[Theantidote]

Yeah did that not so long ago when i change out the oil and filter the second time...probably bout 500k's ago...rear is running rich (according to plugs - confirmed by mech) and front leaner than rear (maybe about right - again according to plugs and confirmed by mechanic)...so was thinking it may need the rear mix tweeking a little...but as i say i'm a bit new and don't want to feek the whole thing on my own...

[nzspokes]

Yeah did that not so long ago when i change out the oil and filter the second time...probably bout 500k's ago...rear is running rich (according to plugs - confirmed by mech) and front leaner than rear (maybe about right - again according to plugs and confirmed by mechanic)...so was thinking it may need the rear mix tweeking a little...but as i say i'm a bit new and don't want to feek the whole thing on my own...

When looking at the plugs did you do a plug chop? Plug chop is riding in the rev range you feel the bike has a problem then pulling in the clutch and hitting the kill switch at the same time. Then pull the plug.

But I would still do the basics like checking float height. Even just swapping the plugs front for back to eliminate them. Air mixture for the idle circuit should be at factory spec which will be a number of turns out from the seat. If the balance was out that would not make that cylinder run rich.

Again, check float height and condition of the float valve.

Will it idle for a long time without changing its idle speed?

[Theantidote]

plug chop yes...i hear what you're saying...idle is great...but after a long hard run (such as to Thames and back) she'll back fire and fart abit when idling...all in all i think it's a minor issue that needs a little fine tuning...and there in lies my dillema...cheap arse single cylinder carbs that have all the adjustment screws easily reached versus my twin carb baby that requires not just a top-a-dect-ame (petrol tank removal) but a very good ear and more than my knowledge (last time i pulled apart a cheap carb i really didn't know wtf i was doing but because they only cost 30$ new no biggy really) at this early stage.
but hei thanks for the support and all advice will be cut and pasted and kept on hand when i grow some balls big enuff to just do it...
cheers

[nzspokes]

I doubt its an external screw issue. Now you say it backfires at idle after a long run? That sounds like a faulty float valve to me. It will be lifting the float level and dumping fuel into the motor. Does your oil smell like petrol? Have you checked your oil level? It may have increased.

[Theantidote]

I doubt its an external screw issue. Now you say it backfires at idle after a long run? That sounds like a faulty float valve to me. It will be lifting the float level and dumping fuel into the motor. Does your oil smell like petrol? Have you checked your oil level? It may have increased.

oil smells good...the more i type on this issue the more things come back to mind...like going to a doctor i spose...could be right...would that be similar too why she don't like the after work run back to drury??? for example a clear run to papatoetoe in the morning equals a crap stuttery run home through slow traffic...but when you ride it harder it seems okay...hmmm float valvey things maybe sticky coz of dirty carb?? esp if haven't had any attention from PO...???

[nzspokes]

oil smells good...the more i type on this issue the more things come back to mind...like going to a doctor i spose...could be right...would that be similar too why she don't like the after work run back to drury??? for example a clear run to papatoetoe in the morning equals a crap stuttery run home through slow traffic...but when you ride it harder it seems okay...hmmm float valvey things maybe sticky coz of dirty carb?? esp if haven't had any attention from PO...???

OK, sounding more like a float valve, at pace on open road the motor will be using the fuel rather than at slower speeds.

Dont muck about with cleaning the valve, I very much doubt thats the issue. Just get a new one from this guy, hes up in Whitford. http://www.smebike.com/about_us

Do it in both carbs, even full kits so you have a great starter point.

[Theantidote]

OK, sounding more like a float valve, at pace on open road the motor will be using the fuel rather than at slower speeds.

Dont muck about with cleaning the valve, I very much doubt thats the issue. Just get a new one from this guy, hes up in Whitford. http://www.smebike.com/about_us

Do it in both carbs, even full kits so you have a great starter point.

hei cool thanks soundz pretty logical...had a look at the link lots of stuff which is good to know...i may need to look for some new manifold boots i think as looking at mine they seem a bit like touchem and they'll break condition...
good project for winter...while the tanks off i'll give a re-spray but fully rattle can black this time-may even do some type of art work to brighten her up a little...
thanks again man...
hope to see you on the road again soon..

[cmoore]

hi, had another look and realised this is the 91...with the Mikuni carbs, mine has the Hitachi, i did however find this thread if it helps

http://www.advrider.com/forums/showthread.php?t=347184