Low speed surging

[Engineer]

Another question

The speed that was appropriate at the time !
I t is irrelevent as the issue is the fueling and mechanical sympathy not the speed and if you can maintain a steady 30 mph in a town centre then you are better than the perfect bikes you have

Well I am gobsmacked, if you can't maintain a steady 30 in town (when the road is clear) without constant gear changing or throttle tweaking then either your bike is broken or you are on drugs I suggest that you buy one of those Honda DCT contraptions, it will take away the difficult gear changing issue and just leave you with the throttle to apply all your concentration to

 

[Engineer]

Simples - ride at 30mph in third and engage cruise control. If the bike stops accelerating / decelerating then it's your hand and you need to consider if you have early onset Parkinsons.

 

[ChazzyB]

No - the mode cannot change the engine revs for a given road speed - the bike has 6 fixed ratio gears so it is not physically possible. I can see that you are not mechanically minded

 

[RedRick Esq.]

Well I am gobsmacked, if you can't maintain a steady 30 in town (when the road is clear) without constant gear changing or throttle tweaking then either your bike is broken or you are on drugs I suggest that you buy one of those Honda DCT contraptions, it will take away the difficult gear changing issue and just leave you with the throttle to apply all your concentration to

Just remind me in my post where i said the road was clear ?

 

[Deleted account 211025001]

The bike holds a constant 30mph in 3rd at constant revs so where is the surging, hunting? The OP found it difficult to hold a constant speed - if you also find this difficult I suggest that it is operator error not the bike?

Is that a bit like the WC's hit and miss gear change/clutch drag that, according to you, is also all down to operator error?

Andres

 

[RedRick Esq.]

As has been mentioned

The fueling on BMW 1200 boxers is alarmingly lean whether you realise it or not ( except Engineers bike or any of his bikes as his finely tuned in built Dyno has, whilst on his daily commute all year long from his girlfriends ( who is also Just wonderful ) , deemed them just perfect in every way and without a single minute fault ) This is to get around the EU emissions regs and also goes a long way to explaining the flat spot in the power curve at about ( but not exclusive) 5000 revs. Engineers bike does not have this as his oh so sensitive inbuilt dyno says so. On his bike the rev counter never varies at tick over it is rock solid in position not a flicker of a rev above the perfect tick over speed.

I guess He is just lucky and should advise us as to when he is parting with his old bikes so us plebs can get a used but perfect uncorroded,snickety gearboxed and immaculately fueled bike with the added bonus of his girlfriend may have once sat upon it.
Why he isnt Motorrad chief quality control officer is beyond me. Not to mention the perfect way in which they have been ridden ( i do not include his girlfriend in that bit)



It is this poor fueling on everyone elses bikes that can ( other problems are available) cause the issue in the OP

 

[Engineer]

To return to the OPs question, surging to the point where you cannot hold a steady 30mph in third gear is not normal for the 1200GS LC or for any 1200GS for that matter - If you think you have this problem then take it back to the dealer and get them to test ride and fix it because, I repeat, it ain't normal.

 

[J biker]

My 14 plate also surges around 30mph in 3rd, 2nd gear doesnt feel right either. Defo fueling.

Not a major issue but intend to Hilltop the bike later this year anyway. Just need to decide how far to go with exhaust system..

Suprisingly my S1 was near perfect stock. Mts 1200 (twin spark) was also good.

 

[Titto]

A quick google of "boxer twin surging" reveals a billion and one threads dating back years and year; this is not a new issue as has been said and there are a few workarounds in many threads - http://bmwsporttouring.com/ubbthreads/ubbthreads.php?ubb=showflat&Number=88454

The worst I had it on was my R1100S boxercup but my horrific '13 GS LC came a close second. The '14 GSLC replacement bike suffered less from it after the dealer (Pidcock) gave it a plug in update - this was in 2015 so I would image most bikes have this now. At 30mph, 2nd and 4th gears were no problem and holding a steady throttle there was no surging; in 3rd the bike would hunt / surge slightly but was enough to be noticeable.
My dads 1100RT then 1150RT suffered the same.

The 5 work bikes our team use (4 1200 RT-LC's and 1 1200 RT-TC) all exhibit the same behavior. Our bike mechanic tried to sort it, but (before being snaffled up by a UAE bike race team) could not get rid of it on any of the bikes despite setting them up as good as any of us have known them to be. BMW HQ UK were contacted by him and their reply was its to do with the generic engine map and to beat emissions etc.

Engineer, the sensation is hard to describe but its like the bike is trying to "catch up with itself" or like the bike has a very loose chain that momentarily gains tension then releases it repeatedly.

 

[Engineer]

A quick google of "boxer twin surging" reveals a billion and one threads dating back years and year; this is not a new issue as has been said and there are a few workarounds in many threads - http://bmwsporttouring.com/ubbthreads/ubbthreads.php?ubb=showflat&Number=88454

The worst I had it on was my R1100S boxercup but my horrific '13 GS LC came a close second. The '14 GSLC replacement bike suffered less from it after the dealer (Pidcock) gave it a plug in update - this was in 2015 so I would image most bikes have this now. At 30mph, 2nd and 4th gears were no problem and holding a steady throttle there was no surging; in 3rd the bike would hunt / surge slightly but was enough to be noticeable.
My dads 1100RT then 1150RT suffered the same.

The 5 work bikes our team use (4 1200 RT-LC's and 1 1200 RT-TC) all exhibit the same behavior. Our bike mechanic tried to sort it, but (before being snaffled up by a UAE bike race team) could not get rid of it on any of the bikes despite setting them up as good as any of us have known them to be. BMW HQ UK were contacted by him and their reply was its to do with the generic engine map and to beat emissions etc.

Engineer, the sensation is hard to describe but its like the bike is trying to "catch up with itself" or like the bike has a very loose chain that momentarily gains tension then releases it repeatedly.

I hear what you say and I know that it was an issue years ago with the single spark 1150s, 1100s were before my time BUT seriously it hasn't happened to any of my 1200s, especially nothing in 3rd gear, it is a doddle holding a constant 30mph.

Maybe I live a charmed life or something

 

[telbenj]

I hear what you say and I know that it was an issue years ago with the single spark 1150s, 1100s were before my time BUT seriously it hasn't happened to any of my 1200s, especially nothing in 3rd gear, it is a doddle holding a constant 30mph.

Maybe I live a charmed life or something

After reading this thread I thought I would check my 2015 GSA and it holds steady and smooth no prob even slowing to 25 it was still fine
Terry