Difficult to start at my wits end

[BSA500]

B###and won't idle .Yes I did

[sean]

one thing you might wat to check in your process of elimination put the bike in a dark room and  a spray bottle of water and spray everything mag . ..plug wires , mag end cap etc .....fire the bike up and see if you have any sparks jumping to ground if you find any spark leaks could be part of your problem ....clean everything off and spray wd 40 it will dissipate the water ...good luck

[Triton Thrasher]

I've  even built up the front edge of a TT slide with solder as a (very) temporary fix to check whether it was too lean. 🤔

I have superglued a sliver of cork to a slide, for the same reason.

[BSA500]

As to clear up some questions the mag has had a fresh rebuild new leads,plug caps ,plugs,b7es,pick ups tested no leaks on the electrical side. Carb is a 1 inch monobloc resleeved slide is brass no slop  tight sliding fit. 270 main 106 needle jet 30 pilot needle on middle clip.carb has been ultrasonic cleaned.No leaks around the carb. I think it needs a richer slide but as it's been resleeved it's not just an easy swop

[rocker21]

i never had any luck with resleeved carbs , i usually bin them as they never seem to work as well as the originals and as for fitting a different slide if needed thats very dificult because that has to sleeved  as well. my fieldmaster had one when i bought it could not get it run properly and in the end i junked it  and fitted one of the JRC carbs , what a difference it now runs as it should.

[BSA500]

Now it won't bloody start 10 kicks plus and when it does it runs fine. Back to the drawing board ffs

[muskrat]

G'day 500.
Yesterday won't idle, today hard to start!
You haven't told us what ignition timing you set it at. Manual or auto advance?
Cheers

[BSA500]

Ignition timing is automatic set using a 'growler'box at5/16 btdc as I always have. When it's going runs really strongly. It must be something I have done to the carb when I was cleaning and reassembling. Since all these mag issues the starting has been a many kick affair, I thought it was the timing was a little retarded but the engine runs really well,when it starts. It's like at the pilot settings no fuel gets to the engine as if there is a barrier.
I need to take the xarb off

[BSA500]

OK stripped the carb down nothing amiss. All clen inside,nothing loose, no leaks on the flanges. Got her to start after about 15 kicks  and  sounded fine but had to hold it on the throttle stopped straight away then difficult to start. So check reset timing again ???

[BSA500]

As the title says. A7 built to Ss spec alloy head 1 inch etc. Now it's had a recent rebuild mainly new pitons rings magneto rebuild by Andrew at Priory magnetos all pretty standard stuff. Bear in mind I have owned this bike for 30 years and I have never had this much trouble starting her.
Now as it stands I have 150 psi on both cylinders beautiful sparks on brand new plugs all leads and picks brushes are new and tested.Carb is clean and no leaks or wear. When she does start and run she pulls well and strong,but it can take 20+ kicks to get there.
Could this just be the timing a touch out??.I have just never had this much trouble setting her up

[chaterlea25]

Hi All,
It sounds like it is not getting pilot mixture?
Are the two tiny holes in the body clear, they go from the pilot up to the engine edge of the slide and another a little further in..
A friend's A10 was doing similar things a while back,, eventually we found that the slide block was loose in the body allowing air to leak in and not sucking up the pilot mixture

John

[RDfella]

That's not timing. Try another carb.

[muskrat]

G'day 500.
Can you get your hands on an Ultrasonic Cleaner. They work wonders for those tiny holes you can't get a pubic hair through.
I have one similar to this, https://tinyurl.com/rwcrpp49
Lots of posts about them https://www.a7a10.net/forum/index.php?action=search2
Then RD's suggestion of another carb sounds good.
Cheers

[muskrat]

G'day 500.
I can hear your frustration! Thanks for asking this here instead of your other topic
To 100% eliminate timing I'd (and do every time) use a degree dick under the cush nut and strobe light. Then you can tell exactly what your full advance and retard is. Also see that the auto advance is working properly.
Cheers

[RDfella]

How old is the petrol? After a couple of months, modern fuel can become a bitch for starting, but engine runs OK when started. If it pulls well, it ain't a timing issue. Plug gaps correct - ie not the standard .025" (or worse still, todays 1mm) ? Plug caps not the resistor type? Those not only reduce the spark, but raise stress in the mag.