44 replies to this topic

[openroad]

I see, so you didn't fix the problem then.

Sooooo, are ya gonna be setting the fuel levels next ? Seems loike a good place to start.

update people.

she purrs. a little higher than i normaly have it it's at 1250-1350rpm but i'm ok with that. had a tinker with the fuel mixture screw. got to balance the carbs but that can wait for a bit because i want to go out and play. just need to run the bike and make sure it runs till i have to turn tap on reserve. how many miles are people doing before they switch to reserve?

[Studley Ramrod]

There are 2 'fuel mixture screws' aka pilot screws, one for each carb. The screw inbetween the 2 carbs is the balance screw.

150 miles to reserve

[openroad]

There are 2 'fuel mixture screws' aka pilot screws, one for each carb. The screw inbetween the 2 carbs is the balance screw.

150 miles to reserve

yer sorry should of said screws. thanks studley i'll have to check the milage nexts fuel fill.

[LDRider]

Yeah, I get about 150 miles to resv on the MK1 unless I ride it like I stole it.

[hammerman]

150 miles to reserve sounds about what I get, I normally start looking for somewhere to fill up at 120 miles, means I never get caught out. I did that in France the other year, thought I could leave it until 150 miles before filling up, then couldn't find anywhere to fill up for another 30 miles after that. It was raining and dark, not a great situation to be in.

[bobsport]

So what was the problem then was it the : float height? as im having pretty much the same problems with my mk1

[Studley Ramrod]

Do you mean the high idle problem Bob ?

[openroad]

So what was the problem then was it the : float height? as im having pretty much the same problems with my mk1

the carbs was overflowing to start with so had to adjust the float height to stop that but when i did start the bike it was idling over 1500rpm and i could not lower the idle speed anymore on the idle knob nexts to the fuel tap so i adjusted the fuel mixture screw on the carbs which droped the revs i got to adjust it a bit more because its still a bit high and fouling the spark plugs which is causing it to run on one cyclinder till i take plug out and wire brush and it will run fine till i stop for a while which i then got to repeat the cleaning of the plug.

[Rallyist]

the carbs was overflowing to start with so had to adjust the float height to stop that but when i did start the bike it was idling over 1500rpm and i could not lower the idle speed any more on the idle knob next to the fuel tap so i adjusted the fuel mixture screw on the carbs which dropped the revs i got to adjust it a bit more because its still a bit high and fouling the spark plugs which is causing it to run on one cylinder till i take plug out and wire brush and it will run fine till i stop for a while which i then got to repeat the cleaning of the plug.

Sound to me that you have slowed the idle down by richening the pilots to much which is causing the plug fouling, something is holding your butterfly's open a little bit, on any carburated system you should be able to drop it back so that it will stop when throttle rolled all the way back, then adjust throttle stop accordingly.

Edited by Rallyist, 02 April 2012 - 05:49 pm.

[openroad]

Sound to me that you have slowed the idle down by richening the pilots to much which is causing the plug fouling, something is holding your butterfly's open a little bit, on any carburated system you should be able to drop it back so that it will stop when throttle rolled all the way back, then adjust throttle stop accordingly.

well the bike was idling fine till i fitted the fuel pump. thats why i was thinking that the fuel pump was suppying to much fuel and i need to adjust the fuel mixture. if i pull the plug out of the the vacume pipe the revs would sky high making me think that it's too rich and the extra o2 coming from the vacume pump causing this. hence why i'm trying adjust the the fuel mixture. but came to a problem when i rounded a fuel mixture screw off. waititng on a new one to turn up and my screw extractors. so i can finish the job.

[Studley Ramrod]

The pump shouldn't make any difference whatsoever to the air/fuel mixture. All the pump does is fill the float bowls with fuel.
When you replaced the pump you also removed the float bowls and floats and adjusted the fuel levels and tweaked the pilot screws.

You really need to set the carbs up to standard settings and replace any worn parts such as pilot screws, emulsion tubes, choke plungers, float valves before you start tweaking the settings. Otherwise you'll just be wasting your time going round and round in circles.

The plug fouling could be caused by worn emulsion tubes and if they're worn, you'll never get the carbs set up until you fit new ones.

In the past I've ragged my hair out trying to set carbs up that have worn parts in them, much as you are now. I've also spent money replacing carbs after I've damaged them, something you may have to do yourself if you don't get the pilot screw out.
Obviously it's your choice if you decide to take the advice offered on here or not.

[openroad]

RIGHT!!!!! here i go again. my second set of carbs have turned. i've set the floats to 13 mm as shown how to do in one of the posts. i have set my fuel mixture screw to 2 1/2 turns from the seated position to start. i've cleans the inside got rid of any muck i found. i've looked a the emulsion tubes they look fine nice and round. i've checked the black rubber slider diaphragm and there is no holes in them. is there anything else i need to check before i put the carbs on the bike?

oh there is two things that is bothering me and i will have to check with the old carbs i got:-
1) the the white washer on the needle with a circlip is at the highest position(shown in pic below) out of the 3 groves. is that right because the old ones i think was at the lowest?
2) i'm sure there is a washer in the bottom of the black hard slide thingy which the needle passe through and on these new ones there is't. is this right?




while i'm posting on this subject. if the emulsion tubes on the old carbs are ok would i be able to use them on these carbs if these get worn in the future. just a thought. be handy to have a spare set .

[Studley Ramrod]

You could check the choke plungers to make sure they aren't worn out.



http://www.carpe-tdm...amp;hl=plungers

The clip should be on the middle notch with the white washer below the clip. Depending on who you believe, the metal washer should be in one of two places



but yeah, there should be a metal washer, are you sure it's not stuck inside the slide thingy ?

Yeah, no reason why you can't use the toobs from the other carbs.

[openroad]

cheer studley. is the choke plunger you posted up a worn one. so i know what to look for.

[dapleb]

Please use ADDREPLY button to avoid duplication of piccies. Ta.

[Studley Ramrod]

Try looking in the linkydinkydoo I posted.

[openroad]

i've checked the choke plungers they look good. while i was at it i checked the plungers on the old set of carbs i had, they was in a right mess as if some thing was eating them away. i've moved the circlip to the middle grove out of the five groves that was there and white washer under it also put the metal washer under the white washer so it rest in the bottom of the black slide as the haynes manual picture shows on the previous post. TOMMORROW AFTER WORK WILL BE THE DAY I FIT THE CARBS. cross fingers and all with the weather and hopefully i can get the bike running again. I shall take the spark plugs out and give them a good wire brush to give eveything a good start.


HAS ANYONE GOT ANYTHING ELSE FOR ME TO CHECK BEFORE I FIT THE CARBS.


THANKS STUDLEY AGAIN FOR THE HELP.

[Studley Ramrod]

Did you check the movement of the pilot screws ? I'm assuming you did after the scenario with the previous carbs.

Fingers crossed for ya

[openroad]

yer i did. i made sure every single screw was sprayed with wd40 and loosen them and did them back up.

update fokes. and i am not just touching wood i'm holding on to a log for security. i fitted the the carb and tweaked the pilot screw a little. still got a little de- tweaking (3 1/2 turns not 2 1/2 turns) but it is running fine and just got back from a blast up the road and it is pulling in all gears. got to oil the throttle cabel but it is all good. i'll make sure the bike starts tomorrow and the plugs havent fouled just incase, but at the moment eveything is all good. oh and i've fitted a set of 30mm bar risers for comfort. so one happy bunny.

Edited by openroad, 13 April 2012 - 07:28 pm.

[Sidarta]

Here's how I did a pair o carbs off a mk2.



Obviously the bowls are different for the mk1 and the fuel level should be 7.4mm to 8.4mm above the float chamber line.

The float chamber line is the lowest line on the bowls shown in the piccy below.

When you connect the tube, make sure the float bowl drain off screw is unscrewed a good few turns and also make sure the fuel pump is connected and the ignition switched on.

The bike also needs to be upright and on level ground.

Regarding the high revs, it might be worth disconnecting the idle speed adjuster from the frame and seeing if it'll turn, they sometimes get twisted up and won't turn freely.

Why have you fitted the leccy pump when the vac pump was fixed and working ?

Hi Studley Ramrod!

Once again I am counting on your help

The photo below shows the first level settings float (7.4 to 8.4 mm) for a MK2 carburetors
(You and I have a 2000 a 2001 - are identical?)

Below is a post # 17 "Hammerman" that are orientaçõs for a MK1, where he wrote: Turn the screws fully clockwise Until lightly seated, then back Them Out two and a half turns (three is the standard setting for the Mk1). Start from there, the more turns in October Richens mixture.

I understand that with the guidance of the "Hammerman" we have:
For MK1 - mixture screw by turning counter clockwise = more air and less gasoline = Richens
mixture screw by turning clockwise = - less fuel and more air = poor
This information is the opposite of what I ever did in all other motorcycles I had (other models). For the screw thus controls the passage of gas and would control the normal air inlet. That's right, for the MK1?


For MK2 (2.5 turns standard?) Controls the gas or air screw?
rotating counterclockwise =? ................
Turning clockwise =? ................

I am very grateful if you can satisfy my doubts

Thank you vey mutch!


Siddhartha