This Forum is now CLOSED use the link to get more details viewtopic.php?f=3&t=13924#p102587
#96295
..because i'm worried that, after almost 1000km running in the overhauled engine, i have to shift back to 3rd gear with strong wind ahead. (19T sprocket, M20 muffler, open air filter 30mm carb)

I checked the advance system for being stuck. I can move it with my fingers, but it stays 'stuck'in any position.
Shouldn't it slide back to idle-position on its own?

Before assembling, i cleaned and mildly lubricated the sytem.,
#96302
They don't like a headwind and on a 19t sporcket, I'm not surprised at all that you need to change into third. Situation normal.

The auto-advance should spring back to fully retarded when released. Most likely thing is you have too big a washer under the central allen head bolt which could be binding against the face of the cam. Try removing that bolt and see if the problem goes away.
#96308
I agree, 19T will be over-geared for an otherwise standard 500 engine.

Ref the advance/retard unit, it should indeed move back by itself as the revs drop, so my learned friend is probably on the money.

Did you get your Polini carb jetting sorted?

A.
#96310
Thanks both for reply, I took an other look and the advance system does release, comes back if the cam does not push the contact breaker up. (if it does, it stays in any position).

The cam has back/forth play, i was thinking about adding a thicker ring or shim to prevend the cam sliding too much over the spindle.

I flowed the head, mounted an open air filter (pic) M20 exhaust (absorbtion) and 30mm carb, i was hoping for a little extra power..
Musta dmit that carb is still not adjusted right and - i guess- is very rich at the moment.
Attachments
oko30.jpg
oko30.jpg (167.06 KiB) Viewed 1582 times
#96311
Adrian wrote:
Mon Apr 12, 2021 8:11 pm


Did you get your Polini carb jetting sorted?

A.
No, the polini really behaves like a 2 stroke carb, an other neelde won't fix it so swapped it for the exact same one , which is also described as for 2S and 4S, and many German bulleteers use.

However, despite the open air filter and M20 muffler it seems to be too rich on the same jetting 'all the germans' use.
#96320
What sort of contact breaker drive/distributor housing is fitted to your Bullet? You might do better with the type fitted to late export 500 Bullets which has the shaft running in proper bearings, the one shown in your photo seems to be the older type.

https://accessories.hitchcocksmotorcycl ... ges%2F2415

If many German Bulleteers are using the OKO successfully and yours is still running rich, I can't imagine all those Germans wanting to stop and clean their spark plugs every 50km, so you must still be doing something differently from them - pilot air screw adjustment, perhaps? Needle position?

Forgive what I hope is a silly question, but are you running with the cold-start plunger wide open, or at least not fully closed? Check the lever or plunger cable is properly adjusted, and that the thing shuts off properly once you have the engine running.

To make that 19T sprocket worthwhile you need a seriously tuned engine, I would suggest a high compression 87mm piston, a tuned cylinder head and fancy cams, not just a less restrictive carb and silencer, because a stock 500 Indian Bullet engine is still in a very low state of tune. Tuning up the engine then places extra stress on the bottom end, so with that tuning package I would also want a steel con-rod and roller big-end.

You might be interested to know, however, that in the 1990s a UK motorcycle dealer was racing 500 Indian Bullets, still with the standard cams and 6.5:1 piston. They fitted the smaller bore exhaust pipes off the 350 models and LOWERED to gearing slightly from the factory 17T gearbox sprocket to a 16T, to help the engines rev more freely. Maybe your efforts should be heading in this direction? Otherwise enjoy playing tunes on your gearbox. I know the Netherlands are not noted for mountains, but the wind is definitely a thing over there!

Image
Photo: fineartamerica.com

A.
#96321
If it is the type of distributor housing with cast iron bushes, you can remove the distributor shaft (yes, this means removing the timing chest cover and pulling the pinnion off) then tap the timing side bush back out by a small amount using a punch through from the "points" side. When you reassemble, the pinnion will bind against the bushing. Give it a light tap with a hammer and it should seat enough to spin freely and have very little sideways play.

Or you can fit shims on the timing side to take out the play.
#96333
The choke comes back good (no cable choke), with a smaller idle jet (40 ipo 48) setting is 2 full turns out, needle is now in 1 to-lowest position.
Open air filter (see pic) M20 muffler, and flowed the head..

Are the distributor assy's with ball bearings also on ebay?
As for the power, after i sorted the carburation out, will delaying the intake cam 1 tooth help?


A dutch enfield 'dealer'(sells parts) the 500 is very fragile and prone to break itself down.. That's why he doesn't want 500 bullets.

Yes the piston is heavier and more power on the same crankshaft, will tuning the engine further not accelerate this process? (if it is true?)
#96339
Yes, the later distributors are available on *b*y, but out of respect for our hosts, I thought I'd better link to THEIR page for this item!

Retarding the inlet cam by one tooth only really does any good on higher compression engines. With a 6.5:1 piston you'll just lose more bottom end power.

There is SOME truth to the tales of fragility of the 500, the problem is in part an old one: take an engine designed for a particular capacity which runs perfectly happily at that capacity, then increase the capacity for more power so that you can sell it to the Americans and hope the original bottom end will cope!

Motorcycle journalist/rogue engineer Royce Creasey noted of the original Redditch 500 Bullet that it would "go bang if you really use it" and advised fitting a Velocette steel conrod in place of the alloy one to make the engine less disaster prone. Conrod failure normally wipes out a set of Bullet crankcases (No Leon, that one in your picture is a different model!). The Indian 500 Bullet has the same design alloy conrod, with the added delights of Indian metallurgy. They USUALLY hold together until you start tuning the engine and "really using" it, there was an example on this forum a while ago, a carefully rebuilt and tuned engine, the alloy rod let go and bye-bye crankcases. Unless you're constantly revving the nuts off yours in 3rd gear to cope with those headwinds, the alloy con-rod will PROBABLY be OK, if you're worried you can always polish it to remove any stress raisers or fit a steel conrod (with a bit of crank balancing) next time you have the engine apart. It's worth noting that for the Electra-X and more recent EFI Bullets, the factory had steel conrods and needle roller big-end bearings from day one.

The other worry about some of the later pre-EFI 500 Bullets concerns the piston, there is a weakness in the design which leaves the crown liable to break off from the skirt, one of our hosts' forged alloy 6.5:1 pistons should last an awful lot longer.

A.
#96342
If it stays stuck, this could be because of weak springs which is common. If the springs are weak the bike will go to full advance at tick over, which in turn will make the engine run rough. Inexperienced owners will, in some cases, blame carburation problems for poor idling. So its worth checking, or replacing the springs with decent quality ones. It's not a big task to mark up the alternator and strobe the performance of the auto advance unit. I've always preferred the mechanical units, because when they are set up and work properly, greater advance is attainable without the risk of suffering kick back when starting, risking damage to the oil pump drive.

Shop for accessories at Hitchcocks Motorcycles