1996 R1100R tuning question

[phoenixtexas]

Does anyone know of a chip that increases RMP above 6,750 and allows moderate ignition timing adjustment? All the aftermarket chips affect only the fuel end of the equation. The bike has a Techlusion and good aftermarket exhaust with a TwinMax to syncronize the throttle bodies perfectly. This may be a dumb question, but what about the chip from an RS or RT? There may be issues about cam profiles, compression differences and peak torque curves, but the charts of the R, RS, RT show about the same power band around 7,000 RPM. Only the in-line multi-cylinder Jap bikes use very high RPMs to build torque at the upper end, and anyone who has ridden them know what I'm talking about. Try twisting the throttle at 70 MPH in top gear on even a Hayabusa and it sounds like a cow farting and accelerates about as fast.

 

[jdiaz]

You can advance timing manually underneath the front cover and pick up a little pep, but not much. I'm not sure what you mean about "adding RMP over 6750" since the rev limiter shouldn't be turning off the fuel supply until 7700rpm at least, maybe 7900.

Pull the timing plug off the right side of the block and watch the timing marks as you rev the bike. The Motronic sysem has a large dip in timing advance right around 3-4000rpm, but basically goes back to full advance after 4K rpm. It would be hard to increase timing adjustment further IMO.

Personally, the best bang for the buck on this bike if you want more top-end is to go back to the pre-96 heads with the larger intake valves. I think they shrunk from 36mm to 34mm at some point during the run, and it makes a noticeable difference.

I might be remembering all of this wrong however, since I sold my last Oilhead in 1999 or so.

 

[phoenixtexas]

To Jon

A sincere thanks for the response. I checked the service book, which lists 7,700 RPM as the red line (same as my tach), but in an on-line motorcycle magazine article, the red line for this model was listed at 6,750. So now I'm totally confused. I'll probably just live with it until next winter and do some top end mods like you suggested, along with hi-compression pistons and cams. Also, I'll probably call the Plano dealership and ask a tech about what the RPM should be.

 

[EMOTO]

What is your goal?

 

[phoenixtexas]

To Emoto

To get the maximum performance I can from the bike, and this is the obvious starting point -- before I start on mechanical steps like Jon Diaz suggested. A 6,750 RPM redline is like handcuffs on an oilhead. FYI, I'm a former Brit bike dealership wrench who's worked on a lot of airheads, and know what they're capable of. I have a '78 R100 and a 1971 Jack Wilson BSA Rocket 3 (which I built from the ground up) that will smoke the R1100R. My modified airhead has been to California and back 3 times with a total of 79,000 miles and not a single major mechanical problem other than a failed alternator rotor and flat tires.

I understand all about power bands, but at 6,750 RPM, you get too much shifting drop between gears, especially in 4th and 5th, and max top speed from the gear ratios on paper is a little over 120. The oilhead was built to spin, and the stock bike just seems dramatically detuned, I guess for gas mileage and the EPA. When I first got it, it was sluggish, surged considerably and clattered badly on top-gear roll-on. A Staintune and Techlusion have helped a lot. I'm not trying to make a race bike out of it, just want it to "be all it can be," like the U.S. Army says, and I'm not really concerned about gas mileage. Any suggestions will be sincerely appreciated.