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[AndrewA]

Hi all, my '92 standard 500 Bullet has arrived back after an extensive (and disappointingly expensive) refurb after being stood in for a number of years.

A Boyer electric ignition was fitted (along with a new carb, plug, points and almost everything else) and it is just not running right. The guy who set it up had problems with getting the timing right despite the instructions being followed. When it was set spot on as per the instructions it started but ran roughly and backfired, when advanced it or retarded it suffered starting (I think in the end he gave up in and was glad to see the back of the bike).

The issues I am having are that it will start, after a good 10 attempts, then when I ride it I am fighting to keep it from stalling and it misfires and doesn't seem too keen on hills either - a but of an issue here in Sheffield!

I am planning to have a go at setting the ignition myself, so was wondering if anyone had any tips please?

Cheers, Andrew

[mauri]

the boyer bransden is not that difficult to set!



a bad spark plug gives the same symptoms that you describe.



had one go bad recently within 50km of new out of the box.

first the power slowly but surly left, followed be the loss of tick over, and a bit later it died completely after some spluttering a couching.

when cold it would start again with a reasonable but sticky tick over but not much power, and when the heat started to come in the tick over went followed again by spluttering and couching and stopping completely.



put a another new plug in and all was ok again.



its rare these days but it happens.

[Gwilly]

Wowa there, hidden in there are two words, "new carb". Has this been checked for swarf blocked passages?

Jetted correctly for the exhaust and filter setup you have? No air leaks induction or exhaust side?
Fraught with problems sometimes trying to change too many things at once..

Your ignition may be ok but you end up chasing your tail trying to fix what aint broke..
A dyno session may help narrow down parameters..

[John M]

I'm with Gwilly, if the timing has been set numerous times without fixing the problem, perhaps it is time to look at the slow running/idle jet on the new carb, particularly if it runs OK at wider throttle openings.

[AndrewA]

The carb was the last thing to be replaced, the guy who replaced the original said things were running much better with the new one.

I think you are right that I may have pay someone else to take a look following a dyno.

[papasmurf]

General comment about tuning engines. Unless you use a proven kit, (as supplied by our hosts for instance,) it can be a minefield. In my experience if you are going to tune/modify an engine, it is best done one item at a time, and tested before you modify anything else.
"New" components can be faulty/internally dirty out of the box. (Earlier comments on the thread about dirt/swarf in new carburettors is especially relevant.)

[PeteF]

Another case of too many alterations being done at once. You paid someone to do this refurb? It's his problem then surely.

[Dennis C]

Yes, as Pete says, it shouldn't be your problem to sort it, take it back to whoever did it.

[AndrewA]

I'd pop it back tomorrow except I am over 100 miles away.....I am going to get in touch and see what we can arrange as it simply shouldn't be like this after paying good money.

[Tim NZ]

I presume the bike went sort of ok previously?


Personally, I would also want to confirm that the cam timing is correct?


There are a LOT of misguided 'tuners' who have randomly retarded the Inlet cam 1 tooth because once-upon-a-time long long ago, it worked for someones old 350 MX bike...


Even then, with the pre '99 engines there is no guarantee the timings will be accurate? H 3 Way pinnion was intended to accommodate the up to 9 degrees variation in woodruf key slot location on the timing side crankshaft.




Boyer Ignition timing: piston at 10mm before TDC compresion stroke, (not such an easy thing to locate so TAKE YOUR TIME) Stator plate fitted and the pillar bolts in Mid Slot. Align either one of the magnets on the reluctor with hole in the stator plate. CCW rotation. Tighten central cap screw that secures the reluctor.


Then triple check that you do indeed have all correctly aligned!


IF motor repeatedly tries to kick-back on starting retard the stator plate 2mm (= to approx 6 degrees) and try again. If bike starts OK but dose not want to rev, advance stator plate no more than 2mm.


That will get you in the general area to start and run. Fine tune accordingly.