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Skids

Guhl ECU mod

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A question for anyone riding a VFR1200F with Don Guhl's ECU mod removing the restrictions in 1st and 2nd (+ 3rd in the UK):

 

With the removal of the restriction, does the TC kick in more often when accelerating away from low speed or a standstill or is it easy to manage on the throttle and not an issue?

 

Thanks. :beer:

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I've got a 2010 without traction control... so not sure if this helps, but I don't have any wheel spin issues unless its morning/wet, and i get ham fisted with the throttle across painted lines on the road.  The rear will spin up a bit in that situation, but it's never been unmanageable (or unavoidable).  On my 2010, I actually found it more dangerous WITHOUT the GUHL flash.  That is, I would get a sudden rush of power at worst times (full lean, painted lines, wet, etc) and that's when the rear would have the tendency to get squirly.

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Sorry m8, forgot the original models didn't have TC. IF I go ahead with this, I don't want to end up with a bike that doesn't retain the easy riding manners it currently has.

 

Thanks for the reply. :beer:

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I have mentioned this in other Guhl flash related threads on this site. The Guhl flash was very much needed on our 2010 as it had noticeable lag through the early gears compared to the 2012. So we did that upgrade and the bike was much better. Not so much better compared to our 2012 however so we never did the 2012. The DCT on the 2012 was noticeably smoother and less clunky through the first three gears. Anyway, both bikes have been terrific. 

 

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Skids, the Guhl reflash will not transform your bike into an unmanageable beast.  On the contrary, it will make it more linear as Crakerjac suggests.  You will notice the change certainly (that's the point), but you'll accommodate the change within a few miles of riding.  It really is nothing to fret over.  To this day I cannot understand Honda's rationale for the restriction in the bottom gears.  I recommend the reflash, especially if you consider some of the other changes that can be made during the reflash.

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Marsman99, you get where I'm coming from. I am concerned about spending £300+ and getting a bit of a beast. My current 1200 is monstrous, as we are all aware but I am concerned that releasing the restriction may make it far less enjoyable to ride because it's so much harsher.

 

Sounds like my concerns may be misplaced. Thanks all.  :beer:

 

Reason I am asking now is that winter is the perfect time for me to be without an ECU for a month or 2.

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Hi Skids, the Guhl reflash actually does make the bike better. On my 2013 I was having issues of the power restriction coming on, or going off at the wrong time. I did not even notice it the first few months of ownership. Once I got used to the bike, it was there, plain as day, and I thought it was downright dangerous. The benefit of linear throttle response really helps your mental map of how much you can push it, and the T/C will let you know when you're getting near the limit. Before the reflash, I knew where the power dip was, but I never knew if I was exceeding the load in that RPM where it would happen......until it happened. Once the reflash is performed, your bike will be like any other 175hp bike, where it would be unwise to crack the throttle wide open while leaned over in first or second gear, or in the wet. My traction control comes on only in the dry if I try to launch really hard off the line, and I cross the paint stripes in the crosswalk, or if leaned over and really hitting it hard in second gear - let's me know I have exceeded the limits of available traction. I don't ride the 1200 in the rain, but have been caught out in a few showers from time to time. I ride very cautiously in the rain, so I have only had the T/C come on in the same ( X-walk stripes, and 2nd gear corners) in the rain, just at smaller throttle openings. I actually like it better as I now know the "Delta" between dry and wet traction.

 

I hope this helps answer your question.

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RC1237V thanks, it does help.  :beer:

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i hate the TC on my 2012.....i only use it in the rain

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6 hours ago, lshark said:

i hate the TC on my 2012.....i only use it in the rain

Really.... wtf are you doing with it? Riding on gravel or a racetrack?

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This may be a dumb question, and I think I already know the answer, but some confirmation would be appreciated. Does the Guhl reflash totally negate the need for a fuel manager? I'm currently rocking a Z-bomb and a TB Juice Box, but it would be kinda nice to have my gear indicator working right again. An extra 500 rpm on top wouldn't hurt my feelings either. And what about the O2 eliminaters that come with most fuel managers? Do you leave them in or plug the O2 sensors back in? Inquiring minds want to know.

 

D Dave

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Doesn't negate a FI Controller if you want additional map control, but you can have Guhl load in a custom ECU map during the reflash.  The internal ECU fuel map will still be modified by the aftermarket fuel controller within its control band, e.g. +/- a few percent, regardless of the map in the ECU.  Should not need to change back to OEM O2 sensors either, they are ignored by your fuel controller.  The Z-Bomb will be unnecessary and can be removed.

 

If one was not using an external fuel controller and wanted to get a bit of fuel optimization during the ECU reflash, Guhl could load in any available fuel map for the bike.  When I had mine done he loaded in a map from a 2010 with K&N AF and stock exhaust that had some tuning done to it.  Since then he has many more map options...below are for a 2010 VFR 1200 from the PCV site.  

 

Might be an option to have him load in an already optimized map that matches your bike mod's, and then use your FI controller for additional control.

 

There are a few other tweaks that can be made, e.g.top speed elimination, fan temp, etc.

 

image.png

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Thanks for that, it's pretty much what I suspected. My only thoughts on having him modify the fuel map are thinking about if I sold the bike down the line. As we know, aftermarket mods don't necessarily increase resale value down the line. Keeping the stock map would allow me to remove slip-on and Juice Box and sell separately. I've already got the fuel manager installed, might as well leave it for now. I'm looking at the reflash mostly to remove 1 & 2 restrictions and get my gear indicator back from the Z-bomb, raise rev limit, and remove top speed restriction (just because). 

 

Thanks for confirming my suspicions.

 

D Dave

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So a VFR1200 DCT can do the 1/4 mile in 11.5 seconds stock (6spd manual 10.2 seconds) does anyone know what she'll do after a Don Guhl tune? Thanks!:beer::beer::beer:

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On 11/25/2017 at 5:54 PM, Skids said:

Really.... wtf are you doing with it? Riding on gravel or a racetrack?

it is a

rudimentary and crude system.....any lift of the front wheel slams me into the tank.....it really sucks.....i'm not afraid of the bike wheelieing or spinning the tire

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