282 replies to this topic

[dablik]

Gone through a bunch of stuff this afternoon from this thread and cant find an issue anywhere...

 

Pick up coil should read 184-276 ohms @ 20c  more like 15c

 

Compression test cold as bike runs like a bag of poop and leaky thermostat hose. Standard compression (Haynes says hot) 152psi.

Cylinder 1

Cylinder 2

 

Plugs were dry but sooty, you can see i've wiped the soot off the one plug on top

 

Seems to be a lot of contention on the internet as to wether compression is higher/lower cold, seems it may be dependant on engine type !!!!!!

 

Replaced vacuum tubes both inlet stubs, pulled choke apart on the carbs and them's fine, checked diaphragms and was hoping to find a hole, nope, needles okay, checked floats again and float needle, all good, checked fuel level on the bench, all good, fitted thermostat hose clips postman delivered, fit the carbs again, very hard to fire up, had to hold choke out for a long time and no choke no run 

 

And that's all i had time for as had to stop playing and come in for me tea 

 

So 

[dablik]

So sooty plugs suggest rich and then being a fooker to start cold and only on choke suggests lean or am i wrong in my thinking ?

 

Edit....Still popping and backfiring as before... Battery 12.9v

Edited by dablik, 14 May 2021 - 07:18 pm.

[fixitsan]

Maybe it's the carbs ?  

So sooty plugs suggest rich and then being a fooker to start cold and only on choke suggests lean or am i wrong in my thinking ?

 

 

 

On one hand the choke is needed because it's cold, on the other you should expect some sort of running (slow to accelerate)  even without the choke.

 

Does it start warm, or is a warm engine still a pipedream ?
 

[Studley Ramrod]

Did you have both plugs removed when you did a compression test Dabs ?  I'm guessing a cold test would result in a lower reading as the metals expand when hot.

Have you tried adjusting the balance screw at all ?

[dablik]

Maybe it's the carbs ?  

 

On one hand the choke is needed because it's cold, on the other you should expect some sort of running (slow to accelerate)  even without the choke.

 

Does it start warm, or is a warm engine still a pipedream ?
 

 

Very slow to accelerate with choke, starts a little better when slightly warm but still requires choke. Cant get the bike warm enough to run on it's own steam, popping and farting to much and will stall.

Did you have both plugs removed when you did a compression test Dabs ?  I'm guessing a cold test would result in a lower reading as the metals expand when hot.

Have you tried adjusting the balance screw at all ?

 

Both plugs out Studs, bike is too erratic to adjust the balance screw, could'nt adjust the idle screw either, i'm thinking valve clearances need another check or CDI unit playing up, also proved 12v from the starter to coil but knew that anyway as bike turning over and firing..

Edited by dablik, 14 May 2021 - 07:38 pm.

[Studley Ramrod]

Turn the balance screw and then fire it up.   And repeat. Which carbs are on at the mo ?

[dapleb]

You say plugs dry dabs but looks oily viewing on my telling bone. If that is dry soot...it is quite sooty! Both same before wipe?

[dablik]

You say plugs dry dabs but looks oily viewing on my telling bone. If that is dry soot...it is quite sooty! Both same before wipe?

 

Ya need a new phone mucka    certainly dry soot daps and both the same before a gentle wipe wid me finger on the one. Normally either a dirty air filter but none in-situ or running a bit rich, oi is baffled.

[Snowbird]

Comps should show lower when cold normally, did you hold the throttle full open when comp checking?

If only running on choke the plugs would be sooty, not running without choke still sounds like fuel problem once choke is off, I've not had the carbs apart (or even off) on a tdm so can't help much more.

Remind me again, has it run ok since the big rebuild or is this still an ongoing issue?

Edited by Snowbird, 14 May 2021 - 07:58 pm.

[dablik]

Comps should show lower when cold normally, did you hold the throttle full open when comp checking?

If only running on choke the plugs would be sooty, not running without choke still sounds like fuel problem once choke is off, I've not had the carbs apart (or even off) on a tdm so can't help much more.

 

WOT when comp testing Dave, plugs were sooty from last weeks shenanigans so explains why plugs are sooty then, cant imagine what the fuel problem is though as carbs checked numerous times and running of remote fuel tank only.

 

Actually the gauge needle shot around without to much encouragement an all.

Edited by dablik, 14 May 2021 - 08:02 pm.

[Studley Ramrod]

Comps should show lower when cold normally, did you hold the throttle full open when comp checking?

If only running on choke the plugs would be sooty, not running without choke still sounds like fuel problem once choke is off, I've not had the carbs apart (or even off) on a tdm so can't help much more.

Remind me again, has it run ok since the big rebuild or is this still an ongoing issue?

 

iirc it ran ok apart from a stutter at 3500-4000rpm then he broke it. did summat, I forget what, and it's run rough since then.
 

[dablik]

Comps should show lower when cold normally, did you hold the throttle full open when comp checking?

If only running on choke the plugs would be sooty, not running without choke still sounds like fuel problem once choke is off, I've not had the carbs apart (or even off) on a tdm so can't help much more.

Remind me again, has it run ok since the big rebuild or is this still an ongoing issue?

 

Bike ran perfectly for 300 miles on Mk1 carbs, cracked a float bowl and swapped to Mk2a carbs, bike idled fine and synced carbs without issue, under load surging at 3.5-4k, swapped out exhaust to full Micron and bike ran for 50 miles testing if i had managed to eliminate the surging, never happened, bike then started popping and farting, changed carbs back to Mk1 carbs, same problem, checked timing and electrics, same issue..

 

I'm likely going to change the exhaust back to the remus just to eliminate one or the other from the problem.

Edited by dablik, 14 May 2021 - 08:53 pm.

[fixitsan]

Sounds like my mk1 after the vacuum fuel pump failed with a stuck open valve flap, held open by a small piece of something from further upstream in the fuel system

[dablik]

Sounds like my mk1 after the vacuum fuel pump failed with a stuck open valve flap, held open by a small piece of something from further upstream in the fuel system

 

Wish that were my case Chris but, all these issues have happened on the remote fuel supply, might just get some fresh fuel for shits and grins.

[fixitsan]

 

Wish that were my case Chris but, all these issues have happened on the remote fuel supply, might just get some fresh fuel for shits and grins.

Nowt lost by trying it

[Studley Ramrod]

Have you checked the remote tank pipe or filter for any crud ?  Had a spiders web in mine, along with other stuff, which restricted the flow.

[Dickiebig]

Still welcome to try my CDI units either from my bike or my spare

[dablik]

Have you checked the remote tank pipe or filter for any crud ?  Had a spiders web in mine, along with other stuff, which restricted the flow.

 

I pulled the filter out of the T piece today to check but you can see clearly anyway that it's not wedged up in the fitting and the fuel line from the remote flows lovley, loike a tap, frustrating innit..

Still welcome to try my CDI units either from my bike or my spare

 

Hi Dickie, i'll take you up on that offer thank you very much, i'll send a love letter tomorrow 

[Studley Ramrod]

Yup, sure is.

[dablik]

Turn the balance screw and then fire it up.   And repeat. Which carbs are on at the mo ?

 

Missed this, Mk1 carbs on, give it a shot then but oi think it's gonna be wet out furra bit.