Anyone fitted Keihan headers to R1200GSA

[Bendy toy]

The Alra headers will release a couple of bhp and being tapered should maintain the bottom end. Remus are larger bore so expect more benefit top end than bottom.
But the headers are not equal length and Y joint is too far down so don't expect any system to be tuned to suit the engine.
Mine has an Akra full Ti shotgun system. No problems over the last 20K miles. However the joints have all jammed up. It's unlikely to ever get dismantled.

 

[sagalout]

Yeah, I just had this OCD thing where I couldn't be happy with them knowing they didn't fit perfectly. They had siezed in the 4000 miles when I tried to get them off, despite using the paste when I put it together, so quite badly marked now. Having the bracket welded to the Y piece means you can't get the exaust off if the joints sieze, which is poor design really. A separate bracket like Keihans and stock system makes removal much easier

 

[DING-DONG]

it's all about the headers and the Akras unleash a bit more than the Keihans.

Yes my TC had 1k on the clock and made 106@ wheel with akro headers, the guy whom did the Dyno mapped each cylinder individual, it went very well and was really smooth, I'm having my latest TC Hilltopped so ill see how it compares .

 

[DING-DONG]

I'd like to say a BIG thank you to mike (Lord snooty) for sorting the deal out with keihan, if we ever cross paths I'll buy you several beers ma old flower

So today was the day I paid a visit to the man called Mark at keihan, very nice fella indeed, and whilst I was there I asked if they could do me a connector clamp rather then use the horrid bm one on the new headers. It was no problem at all to them as long as I wait whilst marks fella work mate knocked a 62mm clamp up, i offered to pay but he refused and offered it foc .

Unwrapped to find some nice shiny headers, they look a treat .

Removed the original headers, geez the Weight difference is surely felt.

Removed the flapper valve unit and removed cables, i then made 2 plastics inserts to blank the holes left by the cables.

Headers installed, the fit was perfect, ideally you need a spare pair of hands, I used a jack to keep them in situ whilst i loosely bolted them onto the cylinders.

New clamp fitted.

Fitment was perfect to a point they fitted better then the akro headers, I also never used the rear hanger on the headers, mark said there was no need for the rear hanger and so I could not see a point using it, once it was bolted together it's rock solid

Finished !

Time for a test ride, well I didn't go far but straight away I could feel that the bike felt smoother and was more eager to rev quicker.

DOWNSIDE. i kind of wished I had them ceramic coated now to stop the discolouring, Next stop is Hilltop nxt week.

Great product being made by a British company, and a real nice bunch of fellas to deal with.

Dave

 

[APW]

pick mine up Monday next week

 

[Lord Snooty]

Fantastic Dave, I am glad you are pleased with the result, they do look great. Thanks for the pics as well as I am sure they will prove helpful to others.

 

[Greenman14]

End can makes no difference - it's all about the headers and the Akras unleash a bit more than the Keihans. I think stock most TC's make about 88/89 at the wheel as its quoted 110 at the crank. I might be wrong though. Either way I'm happy with the way it drives - it's lost that dip at 5k that it used to have

Just had my TC Hilltopped and with a completely standard system it made 79bhp before and 100 after, which Geoff said was pretty normal. I was going to wait for and fit the headers before the remap but Geoff says the map will adapt to any change to the inlet or exhaust system. Bike feels much better all the way through the rev range and can only get better with a decat.

 

[Pacific]

I've just spotted this thread, am I too late to get in on the deal?

2009 1200GS.

Thanks

Mark

 

[Greenman14]

Collected and fitted mine today, used Nick's excellent detailed guide to remove the flap valve. The headers fit perfectly, no leaks, even the clamps are very nicely made. First impressions are that the exhaust note, with the standard can, is a bit more fruity. Not been out on it yet to see if it's a further improvement on Geoff's remap.

Big thanks to your Lordship.



http://www.ukgser.com/technical/nic...rol valve (BMW R-series, '10 to '13) V1.1.pdf

 

[sagalout]

Not been out on it yet to see if it's a further improvement on Geoff's remap.

It will need remapping again really I'd have thought, assuming you were on stock headers when you and the original remap done?

 

[spm0912]

It will need remapping again really I'd have thought, assuming you were on stock headers when you and the original remap done?

Not according to Geoff, his map will self adjust apparently.

Fitted mine yesterday. Noticeably noisier at low revs (well I have removed the flappy valve!!). Picks up better, feels less restrictive (that'll be no cat then!), and nice and shiny compared to the scabby ones I removed. Only problem now is they make the rest of the bike look dirty so I've ended up stripping half the bike to clean it

 

[robb]

Just get them dirty to match the rest of the bike.

 

[Lord Snooty]

For any newcomers reading this thread, the offer is still on so just pm for the information required to take advantage.

Irony of ironies is I haven't had chance to sort my own out yet - DOH! Had the bike in this week for a recall jobbie on the fuel pump flange and had the fuel strip changed and am off to Ireland in the middle of next week for a week's touring so it probably won't be until June when I find the time.

 

[Greenman14]

Not according to Geoff, his map will self adjust apparently.

That's what he told me. And the headers do make a real difference on top of the remap. The bike picks up much better, particularly on part throttle, and feels proper quick from 6000 revs onwards. I always thought the GS felt the slowest 100bhp/200kg bike I've owned, and I've had a few, but that's all changed now. The closest I can liken it to is a standard WC which had almost the same BHP at the wheel according to Geoff. The way it revs up,is a revelation, I wish I'd done this mod 2 years ago.

 

[sagalout]

Not according to Geoff, his map will self adjust apparently.

If so, that's a big plus over the PCV option, as I changed mine and had to have a new map done, which to be honest is a pain as I'm very indecisive on the end pipe! The map I had done recently was awesome with the Akro with baffles, but feels miles out now I've put the stock exhaust on.

I don't understand how it can self adjust though, as I understood the O2 sensors were only used by the ECU for low rpm adjustment, so how does it know what to map to at higher revs? I'm not knocking it mind, just trying to decide if I should sell the PCV and get a hilltop remap!

 

[Greenman14]

I'm not an expert, and someone who is will come along and say this is rubbish, but I think Geoff sets up the air/fuel ratio and if the exhaust or air filter is changed then the air flow sensor detects higher air flow and the ECU puts in more fuel. I also think the standard map does this but it has narrow limits to the extra fuel it will supply whereas Geoff's doesn't.

 

[Bendy toy]

The ECU will self adjust for stuff such as catalyst removal so Geoff is simply using this ability though probably widening its useful range.
My bike sounds great with no baffles but it's risking a ticket. The 30mm baffles I normally use keep it MOT legal and fruity but a bit much for a longer run. For touring with a pillion I have 47mm angled baffles that plug the pipe ends.
It will be interesting to see if the Hilltop map can cover that range of exhaust flows.

 

[sagalout]

Hhmm, yeah, I still don't really understand to be honest. From what I've read the only way that would work is if you have wideband O2 sensors, which the GS doesn't. Instead the O2 sensors are used at low rpm, then at more power it runs to the prescribed mapping.

Maybe as you say the hilltop map just gives a bit more overhead so it won't run dangerously lean, but it's still no longer running an optimum map

 

[kasti]

Ding-Dong:
I noticed your LED brackets, are they custom made or are they serial production from one of the manufacturer?

 

[wintercat7]

Fitted mine this morning to a 2011 TC.

Easy job and as said previously the fitment is perfect.
VERY happy with the performance after a test ride.
A Lot smoother in lower revs and also much Keener to Rev. Totally recommend them.
I had alredy put in a link pipe but this made much more of a differance.

Thanks to Mike for organising this. Owe you a if our paths cross.