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Discussion Starter #1 (Edited)
I am keen on the idea of fitting an ignition rotor with more advance, or maybe just hacking the stock one. Having looked at the specs, it does not seem there is much room for change on these engines.

The stock rotor fires at 5 degrees BTDC at idle, which is already very late compared to most engines which fire at about 10-12 degrees. Advancing it any more than this would get it very close to TDC which cannot be a good thing.

At maximum advance it is 30 degrees BTDC which is more than the other 900 triples of the era, which were set to 26-29 degrees. Even 30 degrees seems retarded when 35 or so is more common. However, although that figure of 30 degrees could perhaps be improved upon, it seems that a global change would screw up the low rpm timing.

Any thoughts, experiences, insights would be appreciated.

ps my mistake, I just realised that more advance would take the figure further from TDC at idle, which would be a good thing.
 

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"Advancing it any more than this would get it very close to TDC which cannot be a good thing."

Not so, advancing it would put it further before TDC.
I think I know where your confusion comes from.
Advance means earlier or before TDC, retarded would be beyond or after TDC.
Think of it like this: 12:00 noon would be TDC, 11:55 would be 5 degrees advance,12:05 would be 5 degrees retarded.
So 10 -12 degrees would be 11:50 - 11:48 as the clock goes.
 

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I filed the ignitor pickup mount holes to give about 2 deg of advance on my 98 Tbird. It didn't seem to make a lot of difference and certainly didn't cause any tickover problems. (I concurr with the KD's maths) I haven't bothered on the Legend I have now. I can't recall where I read it (maybe this forum) but there was some suggestion that effects of even the Factory Pro 4 deg advancer were marginal. That said I'd be very interested to see some dyno results :D
 

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I am currently running the the Factory Pro 4 deg advancer on my otherwise stock 99 TBS. The engine feels noticeably sharper (better throttle response) and it produces (an even nicer) rasping sound. :D.

I don't wan't to speculate on horsepower gains, but the bike feels quicker, so I wouldn't want to miss it. It was cheap und quickly installed (didn't even have to change the gasket).

By the way I am running 95 octane fuel, no probs so far.

Cheers

Budd
 

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Discussion Starter #5
Thanks for that.. I've been trying to find out how many more degrees of advance the Factory Pro rotor gives but it seems they don't do email:)

The stock timing seems way too retarded- I will have to invest in a new rotor.
 

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Hi,

I guess another way to go is to fit Vernier Cam Wheels? Wilcox use to do them, but I am not sure they still serve Triumph motorcycles - perhaps there is another company's offering?

Ciao,
Geoff
 

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What if....?

This thread has sparked :)D) my curiosity somewhat. After doing a bit of research, it would appear that at lighter throttle/load situations, right across the rev range, our classic triples would benefit in power & efficiency from some more ignition advance by 5deg or even more. And the opportunity to adjust an ignition curve or 'map' would also be useful especially where tuning mods have been made.

An ignitor that takes account of 'load' (say throttle position) as well as rpm would maybe be a worthwhile upgrade. (Some other makes of non EFI bikes seem to have this.) And with an anti-knock system also to provide some (not quite 'foolproof') safety against over-enthusiastic 'tweaking'?

I'm thinking of taking this up as a project. (I've a BSc in Electronics) It will likely take some months to do & fully test. It also occurred to me that a pre-mapped to stock ignitor cheaper than Triumph's $700 offering might be worthwhile too?

If I could offer a user programmable unit for, say roughly $450 or a 'stock' replacement for, say, $300 would that be of interest to other owners ?

Not looking for any firm orders or anything (!), just trying to gauge what level of interest there might be? What d'you think?
 

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Discussion Starter #10
Mike,

I'm sure that at that price you would have a ready market. i don't know how many of the other 900 triples used the same ignitor but it could asdd up to a lot of units.
 

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the thing i see is besides supplying the current market , while parts for our bikes are available today , in the not so distant future , that will not be the case and the aftermarket will have to pick up the slack or there will be a lot of h3's rusting away .
 

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On to something...

Thanks for the replies, just to let you know I've been researching this quite a bit & I think I'm on to something which could be pretty useful.

I won't know for sure until I have a unit fitted & can do some testing but it seems likely that a unit which could provide a 'map' for ignition advance taking account of throttle position (or manifold vacuum) vs rpm could provide noticeable improvements in driveability, power & economy.

It'll be a couple of months before I've anything to report, so I'll come back to this in due course.
 

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Ian

I've added a lot more about this project to this thread:

http://www.triumphrat.net/hinckley-classic-triples/99853-igniter-remap-and-low-cost-stock-replacement.html

The Ignitech programmable ignitor is on the way & I should be getting the Throttle Position Sensor mounting bracket this week. I have all the other bits I need, with the exception of the 'window' timing cover (Triumph tool) to check the accuracy of actual settings. I'll likely go ahead & give it a try before I get this anyway....early next week hopefully. I'll post up on the other thread for continuity there.

Cheers
Mike
 
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