So I have had alot of members asking for a consolidated version of the info found in the "Holy Grail" thread.
I asked one of the moderators if we could set up a thread that only I could post in to keep the thread from getting cluttered up but I was informed this wasn't possible so I am requesting that this thread not be commented on or questions asked in it. If you have questions please feel free to contact me through PM or in the other thread. Thanks for your cooperation in this matter.
So first off let me start off by giving you Don Guhl's contact info, he is a great guy to talk to and extremely knowledgeable with stellar customer service.
Don Guhl
Guhl Motors
102 S. State St.
Ephrata, PA 17522-2411175
(717) 618-4212
Hours of Operations
Mon - Thur 9:00 AM - 5:30 PM
Fri 9:00 AM - 12:00 PM
Sat & Sun Closed
The flash costs $375 (cheaper than some fuel controllers) and that includes free overnight return shipping and comes with LIFETIME REFLASHES you just pay the shipping.
Turn around time is extremely fast if he receives it Monday thru Friday during business hours he will flash it and ship it back out same day... now that is service!!!
Here are the basic options:
1. Exhaust = Duals OR 2 into 1... choose whichever is closest to your setup.
2. Idle= our stock idle is 930rpm after the bike warms up.
He can lower your idle down to 660rpm but most people choose 700rpm so as to avoid stalling.
3. Rev limit= stock rev limits are as follows:
Stock 1st,2nd,3rd gears =5250rpm
Stock 4th gear=5000rpm
Stock 5th gear=4800rpm (this is how the bike is limited to 100mph by lowering the rev limit in 4th and 5th gears)
So if you want to break 100mph you simply raise the rev limiter.
You have the option to raise the rev limiter to whatever you feel comfortable with... its your bike so you choose but remember no one will be held responsible for your choice except you... if you have him set it to 10,000rpm and blow your engine its your fault so be smart about it.
Most people go for 6100rpm there are a few of us a little more daring that opted for 6500rpm... I wouldn't push it any further than this and when you see the dyno map you will understand why.
4. Cooling fan = the stock cooling fan turns ON at 225° and OFF at 221°
You can opt to have the cooling fan turn ON at 205° and off at 201°... this is a great option as heat is a major enemy of the engine, the oil, performance, and it is cooler on the rider sitting in traffic. The thermostat starts to open at 176° and is FULLY OPEN at 203° so by setting the cooling fan to turn on at 205° it will not run as long as you are moving with air flowing across the radiator so its not like your fan will be running constantly.
That is about it as far as options go. These 2 flashes (duals and 2 into 1) have been dyno tested on Scott's (GSK1966) bike with a cobra powerflo intake and freedom performance dual exhaust and then with the same intake and STG 2 into 1 pipes.
Your intake and exhaust play only minor factors, any free flowing intake and exhaust are going to be about the same. If you run these tunes on stock intake and exhaust it may run a little on the rich side.
High octane fuel is recommended with the flash as the timing has been advanced.
Also when you reinstall your ECU be sure the first time you crank the bike to just let it idle until the idle drops down and the cooling fan turns on (this may take 10-15 mins depending on the outside temperature) DO NOT TOUCH THE THROTTLE!!! The ECU is relearning the IAC valve position. If you don't follow this procedure, don't complain about stalling.
Basically Don goes into the ECU'S software and reprograms it and gets rid of the factory restrictions imposed by the EPA to make the bike run as it should if the government didn't make Honda jump through hoops.
The timing has been advanced and the fuel maps optimized to give you the best performance possible. There is no need for a fuel controller this does everything for you with no piggyback controllers required.
We are getting approximately a 30% gain in power at 4800rpm which is massive and power gains through the entire RPM range.
Here is a picture of the Dyno results:
![Image]()
This graph shows all 3 versions Stock ECU(just intake and exhaust)in Green, Dual pipes in Red, and 2 into 1 exhaust in Blue.
I know it is a lil hard to read so here are the numbers:
Stock(intake, exhaust only)= 55.67 HP 71.17 TQ
Duals with ECU flash=63.71 HP 75.05 TQ
2 into 1 with ECU flash=67.50 HP 76.40 TQ
As you can see the power band is not only higher but longer throughout the RPM range.
Also here is a graph showing the HYPOTHETICAL TOP SPEEDS PER GEAR at different RPMs with the stock 200/50/18 rear tire(81.29 inch circumference).
![Image]()
I am certain that I am probably forgetting something and if so please feel free to PM me and I will add the info to this page.
I would like to end by saying that this is the best money that can be spent on this bike Bar None in my honest opinion. I have said it before and you can ask anyone who has had it done, it is like riding a completely different bike, the power that this bike has hidden within it is amazing.
I asked one of the moderators if we could set up a thread that only I could post in to keep the thread from getting cluttered up but I was informed this wasn't possible so I am requesting that this thread not be commented on or questions asked in it. If you have questions please feel free to contact me through PM or in the other thread. Thanks for your cooperation in this matter.
So first off let me start off by giving you Don Guhl's contact info, he is a great guy to talk to and extremely knowledgeable with stellar customer service.
Don Guhl
Guhl Motors
102 S. State St.
Ephrata, PA 17522-2411175
(717) 618-4212
Hours of Operations
Mon - Thur 9:00 AM - 5:30 PM
Fri 9:00 AM - 12:00 PM
Sat & Sun Closed
The flash costs $375 (cheaper than some fuel controllers) and that includes free overnight return shipping and comes with LIFETIME REFLASHES you just pay the shipping.
Turn around time is extremely fast if he receives it Monday thru Friday during business hours he will flash it and ship it back out same day... now that is service!!!
Here are the basic options:
1. Exhaust = Duals OR 2 into 1... choose whichever is closest to your setup.
2. Idle= our stock idle is 930rpm after the bike warms up.
He can lower your idle down to 660rpm but most people choose 700rpm so as to avoid stalling.
3. Rev limit= stock rev limits are as follows:
Stock 1st,2nd,3rd gears =5250rpm
Stock 4th gear=5000rpm
Stock 5th gear=4800rpm (this is how the bike is limited to 100mph by lowering the rev limit in 4th and 5th gears)
So if you want to break 100mph you simply raise the rev limiter.
You have the option to raise the rev limiter to whatever you feel comfortable with... its your bike so you choose but remember no one will be held responsible for your choice except you... if you have him set it to 10,000rpm and blow your engine its your fault so be smart about it.
Most people go for 6100rpm there are a few of us a little more daring that opted for 6500rpm... I wouldn't push it any further than this and when you see the dyno map you will understand why.
4. Cooling fan = the stock cooling fan turns ON at 225° and OFF at 221°
You can opt to have the cooling fan turn ON at 205° and off at 201°... this is a great option as heat is a major enemy of the engine, the oil, performance, and it is cooler on the rider sitting in traffic. The thermostat starts to open at 176° and is FULLY OPEN at 203° so by setting the cooling fan to turn on at 205° it will not run as long as you are moving with air flowing across the radiator so its not like your fan will be running constantly.
That is about it as far as options go. These 2 flashes (duals and 2 into 1) have been dyno tested on Scott's (GSK1966) bike with a cobra powerflo intake and freedom performance dual exhaust and then with the same intake and STG 2 into 1 pipes.
Your intake and exhaust play only minor factors, any free flowing intake and exhaust are going to be about the same. If you run these tunes on stock intake and exhaust it may run a little on the rich side.
High octane fuel is recommended with the flash as the timing has been advanced.
Also when you reinstall your ECU be sure the first time you crank the bike to just let it idle until the idle drops down and the cooling fan turns on (this may take 10-15 mins depending on the outside temperature) DO NOT TOUCH THE THROTTLE!!! The ECU is relearning the IAC valve position. If you don't follow this procedure, don't complain about stalling.
Basically Don goes into the ECU'S software and reprograms it and gets rid of the factory restrictions imposed by the EPA to make the bike run as it should if the government didn't make Honda jump through hoops.
The timing has been advanced and the fuel maps optimized to give you the best performance possible. There is no need for a fuel controller this does everything for you with no piggyback controllers required.
We are getting approximately a 30% gain in power at 4800rpm which is massive and power gains through the entire RPM range.
Here is a picture of the Dyno results:
This graph shows all 3 versions Stock ECU(just intake and exhaust)in Green, Dual pipes in Red, and 2 into 1 exhaust in Blue.
I know it is a lil hard to read so here are the numbers:
Stock(intake, exhaust only)= 55.67 HP 71.17 TQ
Duals with ECU flash=63.71 HP 75.05 TQ
2 into 1 with ECU flash=67.50 HP 76.40 TQ
As you can see the power band is not only higher but longer throughout the RPM range.
Also here is a graph showing the HYPOTHETICAL TOP SPEEDS PER GEAR at different RPMs with the stock 200/50/18 rear tire(81.29 inch circumference).
I am certain that I am probably forgetting something and if so please feel free to PM me and I will add the info to this page.
I would like to end by saying that this is the best money that can be spent on this bike Bar None in my honest opinion. I have said it before and you can ask anyone who has had it done, it is like riding a completely different bike, the power that this bike has hidden within it is amazing.
so was going to add insurance and planned to ship USPS priority mail. What amount would be reasonable to insure that would cover the cost of a replacement ECU if its lost in the mail.. and is USPS the best carrier to go with with cost in mind?
