Today I am mostly hating carburettors!

[fossie]

All caps are new ,there is a spark ...a nice bright spark at all plugs. However to night will swap 2 and 3 over to see if issue migrates .

[fossie]

So this evening I swapped over the leads from 2 and 3 .........no change.
Jmac nice chap he is has taken his carbs off his 650 which we know runs fine and lent them to me.
On fitting jmacs carbs , it ran on 2 to start with ......but 1 and 2 ....so not electrical..

So took the plugs out cleaned them again but purposely put them back in different cyls .......ran on 3 again ...however the errant cyl was now 4! Oh yeah. New plug in 4 ( which was new) and.......

Note smoke from both sides ......equally........

No real reason for this photo except people like pictures of bikes ticking over on 4 cyls ......when they are supposed to.
. The simple problems are the most embarrassing! But the elation is just as rewarding. Yippee.

[fossie]

So this must be the criteria for a Sado masatistic encounter with no safe words !
To night went out to it and it ran on 3 cyl no 4 is AWOL. The carbs were still jmacs and left as they were when it ran on 4 last week. Checked the plugs caps etc....4 is still unacountered for.
Oh and the metallic noise I had before has returned can't make my mind up where it is from. Engine area but doesn't alter with the revs

I need to get these carbs back , so put mine on........now they leak through the equaliser tube for 3&4 , so the floats are stuck !

Next step is a compression test, I suppose any one got one I can utilise?

The step after that is break it!

[jmac]

Have access to a compression tester. Week-end o.k.at yours?

[Uncle Bob]

I have compression tester somewhere and also ColorTune if any use. On my 1100 the little tube things (petrol and the ones with the hoses on) that join the carbs did leak so I swapped in new Viton O Rings end of last season. Left empty since then so I'll see over Easter if that is fixed now or not.

[fossie]

Cheers uncle bob , but jmac swung by this evening ....with a compression tester.
So we checked it out... 1=125, 2=125, 3=75 ,4=140. Aha ! :

Ran it revved the nuts off it but the metallic noise was not apparent though it was not running on all cyls again.

Finally the noise appeared and Jmac applied screwdriver to his ear to find the source , seems to be front left of engine exhaust pipe area , but doesn't chang with revs

Anyway jmac parting words were, if you take the engine out I'll strip it to see what's what ...... Got nowt else to do,
Wota geezer eh?

[johnr]

im wondering if the rings have stuck causing the compression differennces hat you have. does seem odd that the one cylinder not working right has the highest compression. gs motors always suffered from cam end float giving a distinct tinkling noise at certain revs, but it never affected the reliability and they ran on for thousands of miles afterwards.
really should put mine back together.

[fossie]

We've decided to strip the engine as we think that either a stuck valve or stuck ring. So we will pull it apart with crossed fingers. It isn't cam end float it is too metallic for that Cam end is a duller guthud guthud sound , this is more of a guthid guthid noise !

Clearly Brexit to blame........the bike was registered in Berlin , home to Mrs Merkel.....

[johnr]

have you tried pouring a bit of derv down each plughole and leaving it to stand to try and free off the rings?

[fossie]

It has got be something broken, I mean we had all 4 pots running , if fact the bike ran quite well and I have rode it round the block. But in answer to the question no Didn't think of it,