Gas gas 1999 txt carb question

[Teddydanson]

Hi guys

the bike rides and runs fine, obviously I have to put the choke on for cold start, but it never idles properly, starts to scream it’s head of, so stop choke then then slow revs for a few minutes then it’s fine and ticks over ok. Question is? Is this normal? Or should the choke be kept on. 

Also I’ve just had a look at the carb, at the side of the choke lever, there’s a little 5mm clear hose. Looks like it runs under the carb and connects on the other side? Can’t be sure without taking off but looks it

it also has a couple of holes and looks a little brittle... is this a problem or can anyone tell me what it does. Like I said it does run well once warm. 

Ive cleaned and remover carbs before but on mx an small quads. I have experience and spanner time. Just not sure with a different bike and carb

thanjs for any help

Edited April 3, 2020 by Teddydanson

[misscrabstick]

Firstly the little hose, it's a breather hose, the holes need to be there or you will get a vacuum in the float chamber and the fuel won't come out the jets properly, you have 2 options, replace it as is but make sure you cut a nick in it to let it breathe, or run a new hose off each side down the back of the engine and just leave the ends open. Now the choke question, with this system which is basically an additional jet opened by a plunger, the initial mixture is very rich, as the engine runs it tends to lean off a bit and the revs rise usually it's time to turn it off at this point, obviously I can't say without listening if yours is excessive, but this is normal behaviour on all makes of bike using this system.

[Teddydanson]

Thanks for the advice, I’ve put a new hose on and cut it in half. I.e two separate hoses.thrre about 3” each in length. I’ve put one behind the air box jubilee clip and the other is just under the carb. I take it if there just breather pipes they can be any length. I’ve been pondering for the last few hours about stripping it down again. Tomorrow and connecting them back togeather and just put a hole in it... 

[lineaway]

attention. your picture the choke is not in the off position. ITis partially still on. I WILL RUN LIKE CRApola.

[Dragontest]

Check your mixture screw settings  and poss order a carb kit, look on line for trials and tribulations in Shropshire he has some in stock(that's where I got mine, ) hope you have it sorted soon

[Creepytheclutchmaster]

My 1999 txt did the same revs to the moon on first start up with choke then settles down, you just have to be ready on the lever to control the runaway revs.