[johnandpamela]

I talked with one of Highlifter Techs this week and asked how the Control Module was coming along and when they would market it. He told me unfoutunatly that they just scraped the idea completely yesterday for good. They kept running into problems in the low and mid range ends thay they could not overcome. At least I know to quit waiting for them to come out with it. Sorry guys. Damn, now I'm running out of things I don't need to put on my Rinny!

 

[Yellow650Rincon]

Yep, I've known about this for quiet some time.

You haven't ran out of things yet. You still don't have an aftermarket exhaust. lol

 

[WoodsRuner]

If there is enough demand, somebody will come out with one, eventually.

 

[Yellow650Rincon]

WoodsRuner, more than one company have tried this. There is a pretty high demand. I think the program in the ECM can not be altered is the problem. If the demand was extremely high, someone would make a whole new ECM for it which would be fully customizable. Expensive, yes, but can be done that way.

 

[tomrice]

Yellow, you are right. The mapping in the ECU would be hard to change, but the problem with power is in the ignition timing. This can be done before the ECU knows what has happened. Advance the timing at the crank. (Different thread). There is no money in this simple mod (once it is tried and proven). No money to be made for High Lifter and others. I may be all wrong, but the ECU controls info starting at crankshaft position. There is no knock sensor to retard timing, so this should be a simple trick.

 

[WoodsRuner]

Yellow, the program is just that, a program. Even if it is burnt permanently
into a PROM chip, the PROM chip can be changed. If the right hacker, with good knowledge of ignition timing and ECM operation ever tackles it, it can be changed.
Maybe it would require a whole new ECM, but no way it would cost more than the
fancy programable modules they have for sports quads now. Highlifter has tried to do it the easiest way, and failed.

The right person just hasn't tried it yet.

RinDong is right. If we could advance the timing a few degrees (3-6) from idle up, it would turn our Rinnys into monsters. No other mods would be required.

 

[Yellow650Rincon]

But the thing is, the Rincons timing is only 13° BTDC. That's really not that far. I don't know what the others are, but there is room for improvement. I think that 4-6° would be the max before the engine would ping with 87 octane.

 

[tomrice]

If 13 degrees BTDC is stock, then 17-19 BTDC should really make it screem.

 

[Yellow650Rincon]

RinDong, 17-19 BTDC would be retarding it more. BTDC = Before Top Dead Center. And BTDC is retarded ignition. The closer to TDC you can get, is advancing the ignition.

 

[WoodsRuner]

Yellow, you got that backwards. The higher the number BTDC the greater the advance. 13 degrees BTDC is firing the plug 13 degrees before it reaches full compression, "in advance" of full compression. TDC is zero advance, zero retard.
19 BTDC would be further advancing, 7 BTDC would be further retarding the ignition from the 13 BTDC start.

 

[jnbjcoy]

The larger then number before top dead center, the sooner in the cycle you fire the plug, hence you are advancing the timing. RinDong was correct in his statement.

 

[Yellow650Rincon]

Oh shit, my bad. I had it ass backwards. lol

 

[tomrice]

Good expaination WoodsRuner. Think of it as firing the air/fuel charge with piston lower in the bore.

 

[johnandpamela]

RinDong, I am not sure, but it sounds like the ECM did change the timing at different RPM's and that is why they are having so much trouble. Someone would probably have to Revamp the hole thing from scratch to get what they want out of it.

 

[tomrice]

The ECM (ECU?) doens't know the crank position unless the sensor tells the position. If you change this, then the timing is changed thru the whole spectrum.

 

[Yellow650Rincon]

RinDong, yes, it's called the ECM in the service manual. ECM and ECUs are the same thing. Engine Control Module/Unit.

Like you said, when the ECM thinks the cranshaft is in a different position than it really is, the timing will be advanced by adjusting the sensor. It's kinda like adding a timing advance key, just easier and free.

 

[plongson]

13° static advance is actually a fair amount, especially if we have any compression ratio at all. Any more than this will probably make it hard to start, especially when warm. What you have to be careful of is the total advance, and the ECM will control this. You will need to strobe the motor and determine what the total advance is before hand. Granted, the ECM will add the static advance to the dynamic, but three things can change if you go too far. 1.) Hard starting
2.) Pre-detonation (very destructive)
3.) Overheating.
Some of this can be overcome with race gas of 100 octane or better. Just be careful and pay attention to what the motor is telling you. You will surely be trading reliability for performance if you go too far.

 

[WoodsRuner]

I decided to look into the use of keys to start my research.
Since alot of work has been done in this area with the Kawi
650 Prairie, that is where I looked first.

The Prairie has keys available for it from 4 degrees to 10 degrees.
Timing starts at 5 BTDC at 1100 rpm and runs up to 28 BTDC at 5000
rpm in a stock unit. With a 10 degree key, this means 15 BTDC at idle
and 38 BTDC at 5000. The 10 key gives the Prairie kick *ss low range
and flattens it out at higher rpms. There have been considerable problems
with 10 keys on quads that have had a ignition module added on top of the
key. Almost none with the 4 key and module.

If we shift the pulse generator 3 degrees, it will give us 16 at idle.
Not much more than a Prairie with 10 degree key. Honda does not specify
what Rincon timing is above idle, but I have heard they do not advance
as much as others, and even retard it some. I think 3 degrees would be
safe for the Rinny. Six maybe a bit much.

The Rancher is a bigger question, I have not been able to find any published
info on initial or subsequent timing figures for it. But it is a low compression
engine (8.8 to 1) and I would think 3 degrees would be OK for it also. If I can find timing specs, I would know if 6 degrees is feasible.
If anyone can obtain Rancher timing specs, please post.

 

[johnandpamela]

Sorry guys, I think you are over my head at this stage. I'll let you Engineers figure this out and follow your lead if you make it work.