[malky]

These 350 Thunderbirds appear regularly for sale in the U.K.
Usually very low mileage and not much money. I've always thought they would be an excellent base for a trail bike conversion. Any serious mechanical problems? I've heard of premature big end failure, but never from an owner.

[Arizoni]

IMO, they would make a good motorcycle for city riding or riding on a good trail.
They are a bit heavy for any off road riding where things get soft.

As you know, the one in the picture is an AVL.

Although they have some unique problems, like their spark controller, they have several improvements over the iron barrel.

First, they have a steel liked aluminum cylinder so they don't oveheat at higher speeds.
The connecting rod is steel and they use a roller bearing in the connecting rod's big end.
They use a gear type oil pump rather than the ancient piston pump for better oil flow.

A quick way to identify the AVL is to look at the rocker arm covers.
If the joint where they meet the head is angled like the one in the picture it is an AVL.
If the engine and transmission are separate (not unit construction) and the rocker arm covers joint is running parallel with the ground, it is an older Iron Barrel.

The Royal Enfield that is the big seller in India is the new Unit Construction Engine in the 350cc size.  It looks like the 500cc UCE but the cylinder is a bit smaller.
It wouldn't surprise me to see some of these sneaking into the European and UK markets thru a back door somewhere.

[Adrian II]

Ebay UK usually has a least one Thunderbird 350 AVL for sale, they seem to have been imported privately in greater numbers than the 350 AVL Machismo in standard Bullet running gear.

The kick start only models use the CDI ignition which runs independently of the rest of the electrics, so that might be a plus point for turning one into a trail bike. These also have the direct AC powered headlight, so that just leaves the rest of the alternator output to be fed to a regulator/recifier unit with a built-in capacitor (eg Boyer Power Box or its Sparx equivalent) and you can ditch the battery entirely.

The E/S models use a TCI ignition pretty much the same as the 500 Electra-X/AVL Classic, so you'd have to keep the battery even if you ditched the E/S.

All of the ignition components still seem to be available on ebay, as do new barrel & piston sets, I have also seen +0.020" pistons. Same con-rod and big end as the Electra-X, though it ought to have an easier life on a 350. Hitchcock's have SOME parts, the rest are probably still available in India. I couldn't guarantee, but I think they were made in greater numbers for the domestic market than the (mostly export) 500 AVL.

I have been tempted to get a 350 AVL myself on several occasions, but never quite succumbed. No garage room!

A.

[Adrian II]

Just checked, Hitchcock's still have a used 350 AVL engine for sale, looks like an early one which used the Dell'Orto PHBH 28 or 26mm carb instead of the CV Mikarb.

A.

[malky]

Thank you gentlemen, a friend is looking for something more manageable and old school that he can work on and personalise, I think this might just be ticket.

[Adrian II]

Choice of three at the moment, all blue!

http://www.ebay.co.uk/sch/i.html?_odkw=thunderbird&_osacat=422&_from=R40&_trksid=p2045573.m570.l1313.TR0.TRC0.H0.Xthunderbird%20avl%20350.TRS0&_nkw=thunderbird%20avl%20350&_sacat=422#item464f9a3456

[heloego]

And, interestingly enough, one of the Sponsored Links below the ads is for the "Wheel Chair Superstore". 

Sweet prices on those bikes compared to U.S. prices. My Recent Electra AVL purchase was similar, but those rides look in much better condition! 

[malky]

Choice of three at the moment, all blue!

http://www.ebay.co.uk/sch/i.html?_odkw=thunderbird&_osacat=422&_from=R40&_trksid=p2045573.m570.l1313.TR0.TRC0.H0.Xthunderbird%20avl%20350.TRS0&_nkw=thunderbird%20avl%20350&_sacat=422#item464f9a3456

Thanks. I've passed on the info. £1200 one looks worth a punt, seeing as tank, seat, guards, bars etc will get dumped.
Only downside is its the furthest away. I could always offer to ride it home.

[Adrian II]

Malky,

it's not that far from me, you'd be welcome for a coffee or two before the ride home!

They're fairly easy to re-style with stock Bullet parts, here's one another Scottish owner had a go at, though perhaps a silver tank would have looked better:



Heloego,

If the bike to which Malky is referring has been stored outside in the English weather, as the chrome work suggests, it will probably need similar attention to the Electra-X you recently bought.

A.

[malky]

This is what the end result should look like, alloy rims included.

[Adrian II]

If he's throwing the Hitchcock's trials kit at it (the version for the disk front end is slightly different) he could of course junk the slightly bulky instrument binnacle and just fit a single speedometer.

Standard gearing on these is, I believe, 5.3:1 in top on a 16T countershaft sprocket, though I have seen 15T offered if it needs gearing down for trail use.

A.

[Adrian II]

Meanwhile, here's a 4 speed 350 Machismo to add to the mix:

http://www.ebay.co.uk/itm/Royal-Enfield-Bullet-350-Machismo-/142023300396?hash=item21113f952c:g:kV4AAOSwLnBXXcko

Seems to be attracting some bids.

[Adrian II]

Malky,

did your friend ever go for one of these in the end?

A.

[malky]

Malky,

did your friend ever go for one of these in the end?

A.

No, he couldn't start it and decided to buy a new Bullet. I gave him a go of my bike and he loved it. Probably the best decision in the long run. At least I won't get the blame when things go wrong.

[Adrian II]

Is he just going to ride it as is, or is an off-road kit still on the cards?

A.