wild foamy Posted June 21, 2011 Share Posted June 21, 2011 Hey everyone im itching to get back to the UK and take my trusty rusty XJ out for a spin, but before i left i was having problems and id like to try and get to the bottom of it before i start thrashing it like a loonie again. at high speeds (80-100) for extended periods of time it would die, almost asif running lean, during this time if the throttle is closed and opened gradually the bike will recover and run normally up to about half/3-4 throttle, on the first incident it cut out and would not run right until i had left it to stand for about 2-3 minutes, after which it appeared to be fine (by this time i was riding through the town, not at speed). i also experiance a lag when opening from part to full throttle at speed, it will cut back before running up to full power and takes approximately 1 second from it cutting to recovering, i have done a plug chop and to no avail, spark plugs look like overcooked cornflakes which (as i understand) is good. it is running a motad 4-1 system, everything else is stock, theres plenty of oil in it and its never done it to me before up until a few months ago, carbs were also balanced a few months ago as always any thoughts appreciated gents, Link to comment Share on other sites More sharing options...
YPVS TONE Posted June 21, 2011 Share Posted June 21, 2011 Try draining the carb floatbowls first in case you have water in there. Link to comment Share on other sites More sharing options...
jebb Posted June 21, 2011 Share Posted June 21, 2011 Hey everyone im itching to get back to the UK and take my trusty rusty XJ out for a spin, but before i left i was having problems and id like to try and get to the bottom of it before i start thrashing it like a loonie again. at high speeds (80-100) for extended periods of time it would die, almost asif running lean, during this time if the throttle is closed and opened gradually the bike will recover and run normally up to about half/3-4 throttle, on the first incident it cut out and would not run right until i had left it to stand for about 2-3 minutes, after which it appeared to be fine (by this time i was riding through the town, not at speed). i also experiance a lag when opening from part to full throttle at speed, it will cut back before running up to full power and takes approximately 1 second from it cutting to recovering, i have done a plug chop and to no avail, spark plugs look like overcooked cornflakes which (as i understand) is good. it is running a motad 4-1 system, everything else is stock, theres plenty of oil in it and its never done it to me before up until a few months ago, carbs were also balanced a few months ago as always any thoughts appreciated gents, I think you've answered your own question...'its never done it to me before up until a few months ago, carbs were also balanced a few months ago'. Prob must lie there check them again or take back to place that did the balancing. Link to comment Share on other sites More sharing options...
Moderator Cynic Posted June 21, 2011 Moderator Share Posted June 21, 2011 Hey everyone im itching to get back to the UK and take my trusty rusty XJ out for a spin, but before i left i was having problems and id like to try and get to the bottom of it before i start thrashing it like a loonie again. at high speeds (80-100) for extended periods of time it would die, almost asif running lean, during this time if the throttle is closed and opened gradually the bike will recover and run normally up to about half/3-4 throttle, on the first incident it cut out and would not run right until i had left it to stand for about 2-3 minutes, after which it appeared to be fine (by this time i was riding through the town, not at speed). i also experiance a lag when opening from part to full throttle at speed, it will cut back before running up to full power and takes approximately 1 second from it cutting to recovering, i have done a plug chop and to no avail, spark plugs look like overcooked cornflakes which (as i understand) is good. it is running a motad 4-1 system, everything else is stock, theres plenty of oil in it and its never done it to me before up until a few months ago, carbs were also balanced a few months ago as always any thoughts appreciated gents, Hmmmm, sounds like fuel starvation rather than an actual carb problem, yes yes i know that sounds stupid but its where i'd start looking. Tank vent being high on the list Link to comment Share on other sites More sharing options...
barkwindjammer Posted June 21, 2011 Share Posted June 21, 2011 Its a Divvy-ya Divvy Link to comment Share on other sites More sharing options...
wild foamy Posted June 22, 2011 Author Share Posted June 22, 2011 BWJ - it aint a divvy ya loon! its a pre-div, ya know, the good ones Cynic - where is the tank vent located and how can i get to it? on my DT there was a plastic tube coming from the cap but on this one theres just a fuel cap, is theres some sort of screen filter on the petcock or anything like that? Jebb - sorry i think my wording came out wrong, what i meant was that the problem occured a few months before this date (around end of april/beginning of may), wheras the carbs were balanced a few months prior to when the problem started (feb/march time) Link to comment Share on other sites More sharing options...
Moderator Cynic Posted June 22, 2011 Moderator Share Posted June 22, 2011 Cynic - where is the tank vent located and how can i get to it? on my DT there was a plastic tube coming from the cap but on this one theres just a fuel cap, is theres some sort of screen filter on the petcock or anything like that? Honest answer, don't know. It must have one but it could be in the cap (a la TDR) could be part of the tank should be some mention of it in the book? Before getting carried away try the leave the cap loose trick and see if it does it at 80-100 (kph i'm assuming ) Link to comment Share on other sites More sharing options...
wild foamy Posted June 23, 2011 Author Share Posted June 23, 2011 Hmm, im a bit aprehensive about leaving the cap loose at 80-100mph, if it happened to come off theres no telling what damage it could do to other road users/pedestrians/pidgeons... another thing ive noticed is that it may be heat related, when it dies and i pull over the heat radiating from the engine isappears to be more than normal, will get an accurate reading for sure when im back Link to comment Share on other sites More sharing options...
XJ600SBULL Posted June 26, 2011 Share Posted June 26, 2011 How long doe you leave it standing is there any chance of there being some gunk or evaporated fuel if stored for a while in the Carbs? I know mine has that issuenjust waiting for gud weather to get it sorted Yours sounds similar to mine so mite be worth a go. Link to comment Share on other sites More sharing options...
Recommended Posts