1/4 throttle issues

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simmo_24

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hi all,
im new this thing and have just got a xr140, and got some protapers and alloy 1/4 throttle.
i have put it all on, and now when starting the bike with the choke on it sounds like it is revving unusually high, but with the choke off it wont start at all (when cold). i know it wont start without the choke on, and i know that i cant adjust the idle untill the bike is warm, i dont want to warm the bike up with the choke on and do any damage if it is idling too high. i know once the bike is warm i can then turn off the choke and adjust the idle accordingly.

another thing off topic, i have noticed on my frame some extra wiring that has been cable tied upto the frame coming from out of the clutch cover does anyone know what the extra wiring may be for? could it be that it has a IRK? eventhough the current ones arent spose to come with them?

cheers, ben.
 
did the high revving problem exist before you put the pro tapers and 1/4 turn throttle on?
if not go over the cables and check if maybe you have adjusted the cable to tight and it is opening the throttle on you.
(once you set your cable tension have the bike running and turn the bars from full lock to full lock, if the adjustment is to tight it will rev
 
there was no revving problem prior to me changing the bars and throttle.i have checked all cables and the seem to be fine, i can not adjust the thottle cable on the handle bars it is already turned all the way in. before the handle bars the choke never actually worked properly i had to start the bike with the choke wide open and turn the throttle a little. i will try tomorrow afternoon at my brothers and let it warm up a little and see if there is any change. i just hope i dont do any damage internally.
 
yeh im gonna give it shot this arvo,
anyone know about this,

"another thing off topic, i have noticed on my frame some extra wiring that has been cable tied upto the frame coming from out of the clutch cover does anyone know what the extra wiring may be for? could it be that it has a IRK? eventhough the current ones arent spose to come with them?"
 
one thing i did notice when the bike is off. i took off the filter and to my knowledge with cars if you turn the throttle the butterfly in the carbie should open up, this doesnt happen on the bike, although the needle inside the carbie does open and close. should the butterfly also be opening and closing or is this just for the choke side of things??
 
have you fixed the revving problem?? did you put the carbie barrel back in the correct way? because if you put it in back to front then youll have a revving problem that you cant control =)
 
i havent ried it yet. the barrel is in the correct way, to my knowledge it can only go in one way cant it? as there are 2 pins inside the carbie that it has to slid between.
 
yeh there is a big one and a little one... the little on is the guide and the big one adjusts your idle there for if it goes in backwards then the big one will stop the barrel for shutting compltelly leaving in open a tad and the lil one will just slide in or something =)

take your airfilter off and have a look through it =)
 
ok my guess is you have put your new bars on and the cable is getting pulled a little bit because of the higher bars loosen your bars and push them forward abit just to see if this stops it if it does then you know whats causing it.
 
ive worked it out, since the bike is new, the throttle cable hadnt stretched yet, the 1/4 throttle had given it too much tension and had the throttle open which is why the idle was so high with the choke on, i have made a smaller bushing for the inside of the throttle so that it has the right tension now. once the cable stretches abit i can put the bushing that came with the throttle back in.
has anyone noticed that the protapers are a little bit smaller in diameter than the stock handle bars? i thought that was weird.
 
Hi simmo_24
We have found that the factories use a few different inner throttle cable lengths when building their bikes.
This means that when fitting a CNC billet throttle more than often the inner cable is too short to allow the carby slide to bottom out inside the carby base or idle screw.[Causing high revving at closed throttle setting]
What happens then is the cable has no slack and is lifting the slide [in effect opening your throttle for you when you dont want it to !]

A quick fix that works sometimes is to reduce the thickness of the cable locknut a little to get an extra 1mm or so of slack in your outer cable !

We sell throttle cables with few different length inners to rectify this sort of problem.
Cheers Brian
 
brian from maylands is rite i brought the same throttle from him put it on yesterday n my bike did the same thing revn at half revs already i rang him back n got the same advice he just gave u i just undid the cable again at the throttle slide the outher cable back slice the black ruber coating of about ten mil back then u c wire coiled around your iner cable un wind that ten mil to n cut it of slide the black outer cable back up put the cable back in the throttle n it gives it the rite amount of slack idles perfect for 65bucks 1/4 turn throttle is a good cheap mod u will notice thanks again to brian at maylands 4 the advice and good costumer service
 
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i wasted 20 bucks on a new cabel when i got the new throttle didnt need it the stock 1 fit wit a trim back but now i got a spare cable 4 when i snap 1 so al good
 
Mine was the opposite, when i added the 1/4 throttle, the inner was too long n didnt sit in the cable adjusting nut, ended up puttin a loose zip between the adjuster and the end of the cable to hold it out, worked a treat, its all hidden under the rubber boot thing.
 
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