Flat spot around 4K

[Comfy Old Boots]

Not a big deal or an issue, I'm just curious. My 2007 1200 GS rides and runs great. I'm very happy with it but it seems to have a bit of a flat spot when accelerating from low to high revs. It is like there is a flat spot around 4k and then suddenly the power kicks in at about 5K. It pulls cleanly but I'm not entirely satisfied that it's normal. Is this why people get the bike remapped in Hilltop?

 

[RedRick Esq.]

4k seems a little low for the traditional GS flat spot.

My twin cam flat spot was at about 5k or just under but i guess that depends on the bike and yes the hill top thing is what cures it other than that just ride through it

 

[Comfy Old Boots]

Thanks Rick. it might be a little higher, I'm not really sure. As long as it's normal I'm happy.

 

[dave perry]

Cheaper and nearly as good as a "Hilltop" is an accelerator module from www.sol2.be !!

 

[younger06]

I have the sol2be module on my 2007 GSA.......I like it but there are many on here who will tell you that the ECU will have long since corrected the fueling changes that the module has made.
I have it for about 20,000kms and I like it.

Sent from a OnePlusX

 

[Comfy Old Boots]

Only E50 delivered!

 

[younger06]

Yeah, it's a cheap fairly basis gadget that fools the ECU into thinking that it's a lot colder than it actually is which results in it richening (probably spelled wrong) the mixture.
I can also recommend putting decat headers on the bike.

Sent from a OnePlusX

 

[Comfy Old Boots]

I think I'll leave it as it is! If it ain't broke etc.

 

[younger06]

You're welcome to try mine with this gadget and open exhaust if we cross paths.

Sent from a OnePlusX

 

[Lord Snooty]

When I took mine to Hilltop it showed a big dip in the power/torque curve at 4k revs which has been totally smoothed out with the remap.

 

[Reggie P]

Cheaper and nearly as good as a "Hilltop" is an accelerator module from www.sol2.be !!

These are popular amongst the F800GS community where they richer the mixture and make it a better bike to ride . I think the benefits are undoubted.

 

[comberjohn]

I've used a booster plug(same thing) on a K1600. Smoother for a while but then reverted back to normal.
Used it on my TC and couldn't feel any difference.
I've used a Power Commander 5 and currently use AF XiED O2 manipulators on my TC and there is no comparison with a booster plug. A hilltop remap is going to give similar improvements.
I spent £90 on my booster plug, complete with remote temperature probe, and I wanted it to work, too. It doesn't.
The benefits of hilltop, PCV and AF XiED units are well described on the forum by many members.
Any one of them will make the engine smoother and more flexible.

 

[younger06]

Was there not a chap on here that was thinking of offloading his set AF XiED units??

 

[comberjohn]

That's right. His tickover went high and he removed them.
After some persuasion, he refitted them and last I read, he was very pleased with them. Must have snagged something first time he fitted them. The units themselves can't raise the tickover.
Nice try, Keith.

 

[Comfy Old Boots]

So, would this AF XiED plug remove the flat spot I have? Give me better low down smoothness? Mines lumpy down at 1.5-2K.

 

[comberjohn]

Yes and yes.
Around town, I short shift gears at about 2k rpm. On the move, I rarely use the clutch to change gears up or down. Twitch of the throttle and it just moves into the next gear. The 'sweet spot' on my bike is now around 4k rpm.
Basically, it pulls like a train from under 2k up to the red line. I've been down the de cat headers and loud exhaust route but now have a standard system on again. Works a treat when the fueling is sorted.
A remap from hilltop is also highly rated. But, like yourself, the journey for me doesn't make it economical.
The AF XiED units are easily installed and work with the ECU. Can be removed if the bike is sold but I've never seen any for sale second hand. The power commander works well and is cheap to buy second hand, but too many wires and connectors for me.
I've done a bit of a write up on them. http://www.ukgser.com/forums/showthread.php/418381-Standard-vs-PCV-vs-AF-XIED
If you have a week free, have a look at the thread on Advrider.
Roger from Boston was the developer for BMW twins.
http://advrider.com/index.php?threa...o2-sensor-project-and-af-xied-for-bmw.749080/

 

[GORILA]

I recently fitted AD Xied units to my 2013 R1200RT, based on the recommendations on this site. The performance of the bike has vastly improved. I can echo everything said about the units. They are easy to install and need little or no fiddling. I am only on my 3rd fuel tank on them, but find the bike running better as time goes on.
Torque, acceleration and smoothness are vastly improved and I now find that the fuel economy seems better too. Only knock against them is the cost, especially with the poor exchange rate.
However if you can get over that the improvements make it worthwhile.

 

[Comfy Old Boots]

I met do some reading!

 

[Comfy Old Boots]

Hang on... Nearly 400 bucks! I think I'll wait for a while!

 

[Bendy toy]

I have the Power Commander V which is good but nothing like as sophisticated as the AF-XIED or a remap. My eventual move will be for a remap but in the meantime the PCV does the job.