ECU from Guhls/Dyno ready

[dsan1964_imp]

I dont think anyone on the forum has had that done in awhile. Will be good to hear a fresh report.

Thumbs up


Sent from my iPhone using Tapatalk

[dsan1964_imp]

I dont think anyone on the forum has had that done in awhile. Will be good to hear a fresh report.

Thumbs up


Sent from my iPhone using Tapatalk

Thumbs up


Sent from my iPhone using Tapatalk

It’s been wonderful! I really like the all around performance. Runs great!


Sent from my iPhone using Tapatalk

[Cormanus]

That's great. Others continue to be interested, http://cb1100forum.com/forum/showthread....#pid253442

[mec_imp]

I haven't been on the forum in quite a while. I didn't take out my bike from storage last year, but I'm starting to get the itch again. I thought I'd check in on the forum, and came across this thread.

A couple of years ago, my buddy and I brought my 2014 CB1100 EX to Don Guhl's place. The intention was to have it tuned and dyno'd. Just before that visit, I installed the TSR air funnel and inlet kits found on Samurider.com. To that, I added a K&N air filter. I'm told the air funnel kit is no longer available, so I'm glad that I was able to get one. The year before I installed Moriwaki exhaust, which provided a small but noticeable improvement in performance. My hope was the two mods along with proper tuning would yield a significant improvement.

The day I visited Guhl's, the electronics on his motorcycle dyno were not working due to a lightning strike the night before. Don spent quite a bit of time trying to resurrect it, without success. Thankfully, he was able to perform the tuning process on my bike by using the oxygen sensor and system on his midget car dyno, which survived the lightning.

He started with the CB1100 tune he had already developed, which I understand is available for purchase by sending in your ECU. Don told me not to expect the mods I made to have much, if any effect on performance, but after running the bike, he ended up making some significant changes to his normal tune. He also removed the speed limiter and increased the rev limiter to 9,500 RPM. Because his motorcycle dyno was fried from a lightning strike, fine-tuning with empirical data could not be done, and he couldn't offer any test results.

I took the bike for a test ride around his shop, but there was a lot of traffic, and I couldn't really notice much of a performance difference at the time. I never got past 3rd gear, but I did get a bit of a hint when high revving in 2nd. When I got home, things became much more apparent.

I can't really offer hard observations about the torque curve and how much more power the bike has under normal riding, but I believe it to be peppier. What I can say, is that when I go WOT, the power is significantly greater in the high RPMs now. The power used to flatten starting around 7,500 RPMs. Now it pulls hard almost all the way up to the new red line, which is 9,500 RPMs. Now that the speed limiter is removed, the bike will exceed 112.5 mph. I've taken it up to 130 mph a few times, which is easily achievable in 4th gear.

The process of buying and installing the mods, along with the trip to visit Don was not cheap, and most folks might say not worth it, particularly since I was unable to get any dyno results, but I'm very pleased and have no regrets.

[PowerDubs_imp]

Would be interesting to know what he changed vs the standard tune, and if he incorporated any of it backdating.


Sent from my iPhone using Tapatalk

[Houtman_imp]

I fully understand that some riders want more out of the CB 1100 engine but for my riding at my age the standard performance is perfect.

[mec_imp]

Would be interesting to know what he changed vs the standard tune, and if he incorporated any of it backdating.


Sent from my iPhone using Tapatalk

As I understand, aside from the removal of the speed limiter and the red line increase, the tune Don provides, like those for other bikes, primarily affects the fuel mapping. In the case of my bike, the "standard" tune he developed for the CB1100 had to be adjusted to enrich the air-fuel mixture because of the mods I made, which result in more air getting into and out of the engine. I'm pretty sure that I remember Don saying that he was going to save my tune in case someone else made similar mods.

When I went to buy the inlet funnel kit from Samurider, Takashi wrote back saying the kit was sold out and discontinued. I asked him to contact the manufacturer (TSR) and ask if they would be willing to provide engineering drawings so that I could have a local CNC shop machine me a set. TSR refused to provide the drawings but agreed to make another small run. I was able to get a kit at the regular price and was glad that my persistence paid off. It may be possible to convince them to make another small run if there are any other folks interested.

[Ben70_imp]

One of the aspects of the flash that appeals to me is I read on Guhl's website that he can modulate the fuel flow on decel, rather than just cutting it off, thereby eliminating the snatchy decel. Do you know if that was part of your job, mec?

[Dover_MA_imp]

Some of the info on Guhl's web site looks outdated. For instance, under the heading Fuel Injection 101 it says:


Fuel pressure is one of the most crucial settings when working with a fuel injection system. Improper fuel pressure is a leading cause of poor performance in a fuel-injected engine. The fuel pressure setting directly affects the air/fuel mixture. Automotive systems are “closed loop” while current motorcycle systems are “open loop”. In a “closed loop” system, oxygen sensors provide feedback about the air/fuel mixture and the system adjusts automatically. In an “open loop” system there is no feedback to the computer. This means that if the fuel pressure is not properly set, the computer has no way of knowing the pressure and the air/fuel mixture will be affected accordingly.



That's not true for our machines, right? The cb1100ex has an O2 sensor for each pair of cylinders, and I thought ran closed loop at all the normal closed-loop times (warmed up, not wide open throttle, etc). Even my 2019 Monkey has an O2 sensor (in the exhaust port of the head).

I didn't know there were ever any fuel injected systems that didn't have the ability to sense oxygen and run closed loop. Does anyone know of examples of this?

[Ben70_imp]

You are riding one. I bypassed the 02 sensor on mine in 2016. Lots of info on this forum, search 02 sensor.

Ben