Carb Slides

3 years ago I had a 5mmx6mm section come out the front edge of my lh carb. Replaced the gnarled spark plug and the bike un-rideable except for speeds over 50 mph. 2 days ago, the same thing happened to my rh carb, but this time all I had to do was replace the spark plug and go for it. It was only too lean at idle and popped back when the throttle was closed. Had to keep going because I was 740 miles from home. [ when I got home I found a section had come away from the side of the slide which is why it was still rideable ] . This seems to be a common problem and I think if the throttle bodies were built better [ thicker at the bottom ] and the appropriate mod done to the carbs then this might not happen. I also think we are bloody lucky that all we damage is the spark plug.
Does the later premier have better designed slides?
I had been having what seemed like a leanness just above idle, and when I replaced that rh plug, the problem vanished. [ Yes Brian, you were right when you asked if the plugs were OK. They looked good, but obviously one was faulty. When I realised that, I fitted 2 new plugs in Levin ]

Dereck

kerinorton said:

Does the later premier have better designed slides?

Click to expand...

The anodised slides (as fitted to the Premiers) I've bought from Amal appear to have been machined from solid aluminium, they are certainly more substantial than the old forged/cast slides.

I had mine steel-sleeved some 30 years ago and I guess that solves the problem of chipping off. Another reason to sleeve.
Jaydee

+1 on using the billet anodised slides , or the brass hard chrome option

smoother operation and help reduce body wear

ugh pre-Peel had thumb nail size piece of slide get chewed up and spit out yet ran fine after regular slides put in as no anodized available then BUT beside the plug hook the valve lips were damaged too so may not want to pull head to know if can ride ok w/o thinking about more down time expense to come.

Frankie17 said:

or the brass hard chrome option

smoother operation and help reduce body wear

Click to expand...

Is it not true that chome peeled off?

I don't like the chrome ones either. here is one from my bike. it has the chrome coming off along with a section broken off.

The Amal chromed slides had issues, but Surrey Cycles did some earlier and these are fine, have had one in my B25 for 7 or 8 years with no problems. Trouble is working out if you have a Surrey Cycles one, I bought them direct before Amal did any so I can be sure of mine.

Over 15 yr ago I tried to buy chrome slides from vendors who stocked them but refused to sell as they know chrome flake off by then. A Norton can process digest and shit out thin brittle chrome no problemo but the slides then pass too much air

I sent my slides to Lund's for sleeving. Works great, but that plus re-building is about the same price as a new Premiere set. I kind of like my originals on the bike even if they've been modified.

the AMAL chrome plated die cast slides are junk the chrome peels off as per your photo (even new ones straight from Amal are bubbling )

i was referring to the MK1 CNC brass type slides which are hard chrome plated

DogT said:

I sent my slides to Lund's for sleeving. Works great, but that plus re-building is about the same price as a new Premiere set. I kind of like my originals on the bike even if they've been modified.

Click to expand...

Had my original carbs bored and the slides sleeved by Lund's as well, these carbs are still working great. It's true that new Premiere Amals don't cost much more than sleeving and re-building your own with all new parts. Maybe only a little cheaper if the other parts of your carbs are re-usable. If I was dealing with warn out bodies and slides today I'd be giving new Premieres a hard look, but thirty five years ago in that dead spot when Norton dealers were no more and the after market had yet to spool up, and before the internet, it was pretty hard to source parts at all let alone carburetors. An advertisement in a magazine is where we got stuff and that's where I first found out about Lund's service. I think it cost $50.00 per carb. I don't know what a new Amal would have cost even if I'd known where to get one, but like I said those early sleeve jobs fixed the problem.

If Amal had spent a few pennies more and sleeved the carbs as part of production in the first place, a lot of us would still be happy with the originals. Overall a pretty good carb with really only three wear parts, not counting the killer of slide/bore wear.

Thanks Guys,. I have been wondering whether to buy the std slides or the anodised ones. I think my carbs are worn but not sure yet,. Besides my wife has told me not to spend too much money just yet. She ought to realise I used every last thou of rubber on my rear TT100 to get home from Wellington.

Get the anodized slides yesterday to save a lot in the future before bores wear. A slather of grease on slides can tell ya how much they leak to matter though some-one warns against this as risking life and limb on stuck open throttle. The brass chrome plated are even better as their mass helps temper the intake pulses and likely return nicer to closed.

I like the idea of brass ones. Can you still get them and are they available.
I just had another look at my buggered slide just now and see it has lost its guide stubb as well. Amazing it went so well and did not rotate.
Dereck

kerinorton said:

I like the idea of brass ones. Can you still get them and are they available.

Click to expand...

http://surreycycles.com/product/heavy-b ... ncentrics/

http://surreycycles.com/product/s-d-chr ... ass-slide/

you can still buy them in the UK around £32.00 ( $50.00 US )

Amal never actually made the CNC brass chrome option it is an aftermarket upgrade ( Wassell )

But does work very well without the chrome peel issues on the die cast slide