[Adrian II]

Carburetor choice?

I've been thinking about that, I dug out the spare cylinder head a while ago and and ported that too.



Back in the summer I fitted a big Dell'Orto PHM38, you may remember.



But if we're looking at alternative carbs, the name Mikuni has to come up at some stage, Niche Cyle in the US offered me a good deal on a VM38 with XT500 Yamaha jetting, and someone in California was selling the exact manifold which would let me bolt it straight on. Thank you, America!



While finally (unless someone has a spare Keihin FCR39) I needed to revisit the Amal carb options. The 38mm Mk2 Concentric would do the job, though these days you're forced to look around for a used or the odd NOS item if you want one that size. Maybe something more er... classic?







Yep, a GP 1½" carb from Mr H. set up to RE Fury specs, with a good used float bowl off ebay. The issue of the non-matching stud centers (60mm on the head, 65mm on the carb) will need some work, but I filed down the inside faces of a couple of 6mm studs just to get the carb on there. In case you're wonder what happened to the magneto, the engine in that frame is the one which will eventually be used in my wife's project bike but which is the one ORIGINALLY intended for this project.

The spare head might go on the street tracker or my other AVL hybrid.

A.

[tooseevee]

Yeah, we did chamber and exhaust port coatings on all the Fireball heads.
The AVL wasn't really needy for it because it has plenty of cooling ability as it is.
But, there are still some advantages of the coatings, and they don't cost much.

            Here's my '08 AVL head after Ace and Mondello's worked their magic on it, lo, these many years ago. Thanks again, Ace. I've never regretted it. The coating just plain looks good though never seen.

            The only thing I regret now, with 20/20 hindsight, is that I didn't have you install a really nice, little decompressor valve. It is INCREDIBLY difficult to get just past TDC with your foot. In fact I'll say this : "It's bloody imPOSSible"! I can kick start it reliably ONLY after it's been run down the road and is warm. Cold kicks? Impossible.

             Starts cold almost instantly with the button so why worry?

[Adrian II]

Having the carb dialed in correctly must help, and if I ever renew an ignition coil your choice of Pertronix Flame Thrower has been noted.Champion plugs now preferred too! Also, my old Electra-X's starter motor still sits forlornly in the garage, it's yours if the one on your AVL Classic ever goes belly up.

Should the need ever arise, I don't think retro-fitting one of the smaller 10mm decomp valves would be too much of a challenge, Ace seemed to think it was do-able when I discussed it with him some time ago. It has certainly been done with the CGT535 head.

A.

[tooseevee]

            Here's my '08 AVL head after Ace and Mondello's worked their magic on it, lo, these many years ago. Thanks again, Ace. I've never regretted it. The coating just plain looks good though never seen.

            The only thing I regret now, with 20/20 hindsight, is that I didn't have you install a really nice, little decompressor valve. It is INCREDIBLY difficult to get just past TDC with your foot. In fact I'll say this : "It's bloody imPOSSible"! I can kick start it reliably ONLY after it's been run down the road and is warm. Cold kicks? Impossible.

             Starts cold almost instantly with the button so why worry?

            I forgot the damn picture 

[Adrian II]

Yes, it looks like 100 mph just sat on the bench. Still plenty of room for that decomp valve. I think it was a great shame there wasn't more interest in the AVL Fireball at the time, yours will be quite a collector's piece.

How many of these did you do, Ace? They must be a lot rarer than the IB Fireballs?

A.

[ace.cafe]

Total of 3 AVL Fireball heads were done.

Iron Barrel Fireball heads were around 45 total.

[tooseevee]

Having the carb dialed in correctly must help, and if I ever renew an ignition coil your choice of Pertronix Flame Thrower has been noted.Champion plugs now preferred too! Also, my old Electra-X's starter motor still sits forlornly in the garage, it's yours if the one on your AVL Classic ever goes belly up.

Should the need ever arise, I don't think retro-fitting one of the smaller 10mm decomp valves would be too much of a challenge, Ace seemed to think it was do-able when I discussed it with him some time ago. It has certainly been done with the CGT535 head.

A.

            Yes. I believe I'm pretty damn close on the carb dialing. Godknows I've spent enough time at it and experimenting. I get a good idle and really good, smooth road performance.

            BUT, never satisfied, I've made a few changes that I will experiment with when it gets warm. I'm like a crippled up old turtle in the cold.

             Right now (I mean last season), I get a good mixture at a bit less than 1 and a half turns out on the mixture screw (so the 27.5 Pilot must be OK) and I can idle it down suicidally low and it won't die (which I only do as an experiment). I NEVer dies on it's own. I quit worrying about that long ago.

             So I've had the carb off and cleaned and petted, etc., and I have leaned the needle one notch just to see what happens. If it doesn't improve anything I will put the needle back in the middle notch as it was before. Also, because the plug is still a bit blacker than I like to see them, I'm going to try a 1 number hotter Champion plug, but only AFter the needle notch change experiment. The needle change may change the plug. Who knows?

             The plug looked good/OK at the middle notch, but just slightly blacker than I like to see.

             I also have bought a Gunson Colortune and cannot WAIT to play with THAT puppy    From what I read, I'll be able to tune from idle to mid-range in the garage using the colors and that's where I do ALL of my riding.

              Much of my cold kick start problem I'm sure may be me (although it was already a problem in 2014). I've lost a lot of muscle strength plus it hurts like hell now and after 3 or four kicks I'm ruined if it hasn't started. Also I only weigh 124 now at 83 (Birthday March 5th). Also 9.8:1 comp.