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A mate and I have 'inherited' a Zephyr 750, which is in need of some TLC - main problem is it keeps dying. New battery, plugs leads & caps. Bike had been standing for about 4 years, in a dry workshop. We suspect the carbs. Can you you get refurb kits for these carbs? Also, fuel filters? Never had anything to do with Kwaks before, so I I'd be grateful for any links etc.

Thanks

Martin

These peeps have a few odd Zephyr bits. https://www.z-power.co.uk/merchantmanager/index.php Dunno what else used the carbs.

If it's been standing that long the fuel's probably 'gone off' and left a nasty varnish inside the carbs, prolly best to take them off and clean them up, and get rid of any remaining old fuel and fput some fresh in. Also run some fuel system cleaner through the tank once you get it to run.

Have you got the fuel tap set to 'on' ? Try it on 'prime' and see what happens - if it runs then there's prolly a problem with the vacuum fuel tap, you can get a repair kit from NRP Carbs
That's of course if the vacuum pipe is connected?

They're the first things I'd look at anyway.

I would agree with everything BG says for starters, cooking unleaded turns to crap quite quickly, so do your best to clean the carbs out. If it is not too bad you may get away with flushing the tank out and refilling with some super unleaded which does not seem to have the same problems.
Check what comes out of the tank, if lots of loose rust you have one obvious problem. You obviously need to clear this out and clean or replace any fuel filters, as BG says check the taps as they could also be blocked or have problems with the vacuum pipe.
Once on clean petrol, try some carb cleaner in the tank like Redex, or whatever, and it may just clear things enough to fire the bike up. It has worked for me quite a few times.
Keep running it through and see how things go. With some cleaners you can actually squirt it directly into the carbs once fired up.
If it eventually fires clean on all four, keep running with the additive for a while. If no joy, you will need to start stripping the carbs down to get rid of the varnish/gunge I'm afraid.
Good luck with it!

I've heard good things about these people and bought a few jets off them - they do a carb refurb service

http://www.motocarb.co.uk/index.php?_a=viewCat&catId=9

Thanks for your replies. The lad who's 'left' us the Zeph claimed he'd had a go at the carbs, but we know he didn't have the time to do a proper refurb. Managed to find suppliers for refurb kits and diaphragms (can't remember who now - written on the famous bit of paper). We'll see what happens with these fitted, and a proper soaking in cleaner, then delve deeper if we have to.

The tap appears to be fine.

Bit concerned about the effect that gummy residue from the old fuel may have had on the piston rings - any thoughts, please? Way back when, I'd have dribbled a bit of Red-X into each plug-hole (to dissolve/soften the residue), left it a couple of days, then spun the engine to eject the Red-X from the plug holes. Messy, and los of smoke for the first few minutes' running, but it seemed to work. Is there a bettter product or method now?