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Trenchtractor
| | Posted on Monday, December 06, 2004 - 05:16 am: | 
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My thoughts exactly...
If the aftermarket cams available through the likes of NRHS can be used on either bike, with stock injectors and a PCIII or TFi with equal success, I can't see any reason for this not to work.
All the TFi does (IIRC) is extend the injector pulse to add fuel. So long as the injectors are firing at the start of the opening of the inlet valve (which is normal), the fact that both bikes use the same cam would lead one to believe they would begin the injector pulse at arouind the same time. Extending this pulse with the TFi would enable the use of pretty much any of the ECMs in the XB line up.
But still, I wonder about the redline, if it's sustainable as a road application... |
Blake
| | Posted on Monday, December 06, 2004 - 09:21 am: |
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Okay, a few points to consider.
1. Your dealer adjusted the cam position sensor timing. Question: Was it set accurately to begin with or was it off as delivered? That has been the case on some bikes.
2. Your dealer will not be able to reflash the ECM. The effort I described from 1999 was being handled directly by BMC Inc. engineers.
You continue to make assumptions that I would not be comfortable making.
Have no doubt that running and regularly hitting a 7,500 rev-limit on a stock Buell XB12 engine will absolutely compromise engine life. How much is the big question. Intertially induced stresses in reciprocating parts of an engine increase proportionately with engine speed squared. So going from 6,800 to 7,500 rpm will increase inertially induced stressed by over 21%, not a trivial increase by any measure.
If all you are interested in is reducing your XB9's rev limit, I believe there are aftermarket devices that will do that. I could be wrong.
Why on Earth anyone would want to reduce their hard cut-out rev-limit from factory setting is beyond me. Put a programable shift light on the dash. Good grief. I thought you were wanting to increase for performance reasons the XB12 rev limit.
So you would be stressing the engine |
M1combat
| | Posted on Monday, December 06, 2004 - 10:40 am: |
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Lighten up Blake  . I think we all understand that more RPM's w/o changing anything else will add stress and reduce life. If you would like to discuss what Trench's dealer did to his bike, please start a "Trench's Timing" thread. Thank you for your understanding .
This sounds very doable to me. I think as long as we can get the engine running and get no codes and run an A/F meter. If it were mine Id run it WOT up to about 2500, then check the AFV. If that looked good, run it up to about 4000, check it again. If that works, run it to about 6000 and see what the A/F looks like. If that's all good, go for broke . I'm willing to try it. The way I look at it is that I rarely hit even 6K RPM's so I doubt I would hit 7500 much at all. As long as I'm not using that extra rev limit, I'm not hurting anything at all. I think I'll wait until I build a track bike to decide how long the stock parts will last when that RPM level is more sustained. When it goes BOOM, I'll rebuild it with whatever seems best at the time, and then see how long THOSE parts last at those RPM's.
I think it'll work. I think I'll probably try it early next summer. If it goes boom, I'll let you all know . |
Blake
| | Posted on Monday, December 06, 2004 - 11:45 am: |
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Cool.
Hey! Tractor boy started it. Just clarifying that issue is all, wrt the "known unknowns." |
M1combat
| | Posted on Monday, December 06, 2004 - 12:09 pm: |
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Gotcha . I just don't want to see too much thread spread in this particular thread (seems how it's mine and all). |
Oconnor
| | Posted on Monday, December 06, 2004 - 01:13 pm: |
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http://www.electromotive-inc.com/
I still think this would be the easiest way.
Done them before and with their easy start system very easy to tune.
Althoughit would cost about 1500 bucks.
Hmm on to motech maybe? |
M1combat
| | Posted on Monday, December 06, 2004 - 02:49 pm: |
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Oconnor... Search the site for "Megasquirt". Better choice if you want to replace the entire system. We aren't looking at doing that though. Just an ECM swap is all  . |
Oconnor
| | Posted on Monday, December 06, 2004 - 02:54 pm: |
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No, I hear ya, but don't you have to build the mega squirt?
Hmmm plug 'n play. If I had a 12 I'd give it a go. |
M1combat
| | Posted on Monday, December 06, 2004 - 02:58 pm: |
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Yes, you have to build the megasquirt, but if you have the ability to build an injector and spark curve I assure you, you have the ability to build a megasquirt... Anyway, this is beyond the scope of this thread. We are only discussing an ECM swap and the required extra stuff that gues along with it. |
Trenchtractor
| | Posted on Wednesday, December 08, 2004 - 05:42 am: |
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:-) Tractor Boy... lol. Reference to farm machinery when we are discussing HD based stuff... I never.
Blake,
My thoughts on REDUCING the redline of the 9 ECM was more intended for an adjustable redline for a 12. I don't like the idea of my 12 doing 7,500rpm, but a 7,000rpm doesn't sound too bad... What's the Pro series ECM for the 12 redline at?? Would an extra 200rpm be that bad??
A 9 ECM won't need the servo motor attached, and if it does have a less aggressive advance curve than the 12 ECM, guys having issues with pinging could use a 9 ECM with the TFi, giving them a greater redline and redline adjustability... My thoughts, anyway...
Since we are back to the pinging (you'd think I had a one track mind, eh??), the dealer set, reset and re-reset the cam position sensor, the TPS, the idle and whatever else was going for an adjustment at the time... I passed on a miriad of suggestions that were made to my via this board and others, not to mention some mechanic mates and a few of my own theories... All were received well by the technician working on my bike, and any that were too half baked weren't merely dismissed, but explained away...
The setting of the timing retarded was a last ditch effort to try and make some progress. Nothing else that had been done and re-done had made any difference until then, and Buell USA had not provided any solutions. Nonetheless, retarding the static timing did stop the pinging. Like I said, though, it was like this for half a day, just long enough for me to test ride it to prove it wasn't gonna ping on me.
After we proved that the race ECM was the problem, and that it was because the ignition advance was too great, we went to the stock kit (I bought my bike fully race kitted), which also worked. About that time, we finally got an answer from Buell USA that I should fit the stock kit, get a refund for the race kit and be happy. I was not, not with that response, anyway.
At this point I would like to add that the Pro series ECM was swapped outa my bike into another and it's pro series ECM fitted to my bike. There was no change in either machine. They both behaved just as they had before the swap. The same process was used with every sensor bar the cam position sensor (I think it was left out of this type of test).
Thanks for the clarification on the reflashing of the ECM's... Although, word from Fullpower was that an alaskan dealer offered to reflash his ECM... This was news to me and I haven't heard any more on that matter from him.
To get back to the matter at hand (sorry M1), I can see the benifits of using the 9 ECM to provide an adjustable redline for racers, especially the land speed type. I hit my redline from time to time still, depending what I'm riding as well as the XB12, sometimes it just gets to 6,500 all to quick, especially now with the TFi and a few other mods I been throwing at it (Odie and I are running VERY similar machines, I think)... I haven't really been able to ride my bike in the last 2 months, so this morning was the first real thrash and I did use the soft limiter a couple of times... I was thinking a change lamp in the spare spot on the lamp cluster would be neat...
But hey, this is great food for thought, the more I think about having a dial your own redline, the more I wanna play with it... Just it won't be this year. |
M1combat
| | Posted on Wednesday, December 08, 2004 - 10:44 am: |
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Well, my other thoughts were a Crane HI-4E ignition and an aftermarket ECM. I think the 9 ECM may be a better choice though. |
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