R1100RT surge/snatch when riding above 3000rpm

Post your Oilhead technical queries here

Moderator: Moderators

User avatar
Dawntreader27
Forum User
Posts: 23
Joined: Sat Nov 25, 2017 12:52 pm
Country of Residence: UK

R1100RT surge/snatch when riding above 3000rpm

Postby Dawntreader27 » Mon May 21, 2018 12:27 am

Hi again,
I been getting this strange snatch feeling on my R1100 ever since I got it. it feels like a chain driven bike with a loose drive chain when it was slack and make a "Clack" sound. Any ideas what this is??

User avatar
Dawntreader27
Forum User
Posts: 23
Joined: Sat Nov 25, 2017 12:52 pm
Country of Residence: UK

Re: R1100RT surge/snatch when riding above 3000rpm

Postby Dawntreader27 » Mon May 21, 2018 10:11 am

I want to add I have had the bike now for 1500 miles, she pulls like a train and does everything else as she should, except of course for the intermitent "clack" sound when riding around 60 mph+???

User avatar
Dawntreader27
Forum User
Posts: 23
Joined: Sat Nov 25, 2017 12:52 pm
Country of Residence: UK

Re: R1100RT surge/snatch when riding above 3000rpm

Postby Dawntreader27 » Wed May 23, 2018 6:50 am

I guess no one else has experienced this then, so it's off to the workshop with my wallet :pale:

User avatar
windmill john
Forum User
Posts: 3420
Joined: Fri Feb 18, 2011 9:58 am
Country of Residence: England
Location: Somewhere in Southern England. bip bip bip, loose lips sinks ships

Re: R1100RT surge/snatch when riding above 3000rpm

Postby windmill john » Wed May 23, 2018 6:58 am

You might need to describe the clack differently...

Is it the sensation of slack train, .i.e physical and possibly from the drive chain?
I say that because if it is more of a surge, then it could be your fuelling/ignition; or more to the point, Hall sensors.
I used to get a slight bogging when opening the throttle at speed. That turned out to be failing Hall seniors, but the next time it was blocked injectors.

John
http://www.kittos.co.uk
Best roads: 623 Burgos to Santander. A back road to Metz; can't remember which!
Schorsch - 1978-80 R65 - Has gone. No, not talking about it.
Max - 2009 F800GS- where’s the desert at!?
Too many bikes have come and gone, trying to be sensible now!

King Herald
Forum User
Posts: 507
Joined: Wed Apr 05, 2017 3:24 pm
Country of Residence: United kingdom
Location: Midlands.

Re: R1100RT surge/snatch when riding above 3000rpm

Postby King Herald » Wed May 23, 2018 7:47 am

My 1100r has a sort of clonk in the drive train when you gently on and off the drive at low speed, clutch inand out at low throttle, almost like lots of backlash somewhere in the system. The gearbox makes the usual loud klunks when shifting gear so I assume it is related to the agricultural engineering within.

It also judders and surges a bit at low throttle openings but is a lot better after I gave it a full tune up and service soon after I bought it.

Sounds like you also need a full throttle body balance and tune up to eliminate any imbalance between cylinders as well. It helps a lot.
R1100R
Suzuki Bandit 1200

User avatar
Douglas C
Forum User
Posts: 199
Joined: Fri Jul 29, 2005 8:53 pm
Location: South Queensferry

Re: R1100RT surge/snatch when riding above 3000rpm

Postby Douglas C » Wed May 23, 2018 9:28 am

I want to add I have had the bike now for 1500 miles, she pulls like a train and does everything else as she should, except of course for the intermitent "clack" sound when riding around 60 mph+???
Is it related to engine speed or road speed?
i.e. does it do it above 3000rpm in any gear, or only top?
Douglas C.

2000 R1150GS
1998 K1200RS (Now gone)
1994 K1100RS (Now gone)
1968 Triumph T120

User avatar
Dawntreader27
Forum User
Posts: 23
Joined: Sat Nov 25, 2017 12:52 pm
Country of Residence: UK

Re: R1100RT surge/snatch when riding above 3000rpm

Postby Dawntreader27 » Wed May 23, 2018 4:48 pm

Hi it does it intermittently above 3000rpm so cruising etc but rarely when going very fast ie above the Legal Limit. The experience is a judder accompanied with a clonk/clank sound. Other than a backfire occasionally on overrun the bike performs beautifully like it should.
I think it may be a good idea to check the throttle body synchronisation what do you think .
John, the sound is very similar to a bike with a slack drive chain.

User avatar
Dawntreader27
Forum User
Posts: 23
Joined: Sat Nov 25, 2017 12:52 pm
Country of Residence: UK

Re: R1100RT surge/snatch when riding above 3000rpm

Postby Dawntreader27 » Mon May 28, 2018 6:52 pm

OK guys, further info for my post. It does this weird Clunk/jolt thing at 4000 rpm and above.
I can only liken it to being a bit like the snatch on a chain drive bike when the chain has too much play. It does not do it at either high cruising speed or around town speeds.
any suggestions as it is really bugging me.
Thanks

User avatar
Douglas C
Forum User
Posts: 199
Joined: Fri Jul 29, 2005 8:53 pm
Location: South Queensferry

Re: R1100RT surge/snatch when riding above 3000rpm

Postby Douglas C » Wed May 30, 2018 5:09 pm

Sorry, can't really offer any ideas, other than to check everything in the drivetrain to start with.
With the bike on the centrestand, spin the rear wheel listening/feeling for any roughness in the rear bevel bearings. (Any sign of oil leaks?)
Check the swinging arm and paralever bearings for play.
Then onto the engine to check valve clearances, throttle balancing etc.
Douglas C.

2000 R1150GS
1998 K1200RS (Now gone)
1994 K1100RS (Now gone)
1968 Triumph T120

User avatar
oldyam
Forum User
Posts: 642
Joined: Wed Apr 01, 2009 9:33 pm
Country of Residence: Ireland
Location: Ireland

Re: R1100RT surge/snatch when riding above 3000rpm

Postby oldyam » Wed May 30, 2018 7:50 pm

Just something a little off the wall but worth checking, pull back the rubber boot and look up the inside of the swing arm for tiny bits of black on the inside of the housing .......

Sounds a little like the drive shaft rubber bonding may be starting to fail .....
Nigel
1994 Triumph Trophy in British Racing Green
1993 Triumph Trophy in Caspian Blue
1999 Triumph Trophy in Oxford Blue
2007 R 1200 RT Blood Bike Leinster
2000 R 1100 RT in Black ( Sold )
1981 Yamaha XJ650 in Red ( Sold)

User avatar
Galactic Greyhound
Moderator
Posts: 9009
Joined: Sat Aug 28, 2010 11:26 pm
Country of Residence: Scotland
Location: Dumfries

Re: R1100RT surge/snatch when riding above 3000rpm

Postby Galactic Greyhound » Wed May 30, 2018 11:15 pm

oldyam » Wed May 30, 2018 6:50 pm
Just something a little off the wall but worth checking, pull back the rubber boot and look up the inside of the swing arm for tiny bits of black on the inside of the housing .......

Sounds a little like the drive shaft rubber bonding may be starting to fail .....

Click to Enlarge/Save As:
Failed driveshaft rubber.jpg
Failed driveshaft rubber_2.jpg

See if you can reproduce the fault as follows:

1. Bike front wheel against a wall on a hard surface, Neutral engaged, Engine running.
2. Clutch in, Select top gear.
3. Front brake on HARD, keep as much weight as possible on the seat over the rear wheel - consider using a pillion passenger.
4. Release clutch slowly while increasing revs and try to load the transmission with full power without spinning the rear wheel or burning the clutch - see if the 'clack' can be induced to happen.
You do not have the required permissions to view the files attached to this post.
Ced.

R1100RT 1996.
Sent by Boson Quantum Transmission from the Starship 'Galahad'.
http://www.researchgate.net/publication ... ing_bosons" - It works!

User avatar
sykospain
Forum User
Posts: 130
Joined: Sat Apr 15, 2017 12:42 pm
Country of Residence: Spain
Location: ALAN on the South Eastern Med coast of Spain
Contact:

Re: R1100RT surge/snatch when riding above 3000rpm

Postby sykospain » Tue Jun 19, 2018 5:09 pm

Hesitance, back-firing, jerkiness, clacking sounds from the drive train....
As somebody says elsewhere in the world of BMW boxer-bike forums :-
"It's ALWAYS the effing stick coils.."

But maybe your older bike doesn't actually HAVE ignition stick coils stuck in the roasting atmosphere of a tight tunnel leading along to the spark plug ?

But if it DOES, find a pal with a similar bike, pull a stick coil out using that neat little 3rd-party alloy puller, not the brittle plastic garbage that comes with the toolroll, and swap a coil, or maybe both, from your pal's bike to see and feel the instant improvement.

I betcha....
This is the list of people I'd trust with my bike.

Mike D
Forum User
Posts: 1650
Joined: Thu Oct 18, 2007 3:12 pm
Country of Residence: UK
Location: Near Daventry, UK

Re: R1100RT surge/snatch when riding above 3000rpm

Postby Mike D » Tue Jun 19, 2018 6:18 pm

R1100RT and single spark R1150RT do not have stick coils.

Mike

User avatar
Galactic Greyhound
Moderator
Posts: 9009
Joined: Sat Aug 28, 2010 11:26 pm
Country of Residence: Scotland
Location: Dumfries

Re: R1100RT surge/snatch when riding above 3000rpm

Postby Galactic Greyhound » Tue Jun 19, 2018 6:47 pm

.... and if you don't have stick-coils it's always the HES :lol:

Seriously, if you are getting unexplained back-firing, surging/snatching on an R1100 or R1150 after checking all other possible causes, then consider changing the HES Trigger Unit especially if the bike is approaching 50,000 miles and the HES has never been changed.

The wiring insulation in the HES Trigger Unit sub-harness degrades over time and messes up the square timing pulses for the fuelling and the ignition.
There are TWO pulse streams sent from the twin HES sensors to the ECU - one (top HES) is for the ignition, the other (bottom HES) is for the fuelling.

If any of these pulses streams are degraded, the ECU (Motronic) has a hard time trying to figure out the injection and ignition timings.

The backfiring/jerking is a clue - the HES ignition pulses can fail momentarily and the unburnt fuel gets pumped into the silencer where it is ignited by the next hot exhaust gas as the ignition comes back on line.

The HES Trigger Unit on Oilheads MUST be changed before 50,000 miles occurs or failure can be expected shortly afterwards.

If it fails for the first time when on the road, then do NOT flatten the battery trying to restart.
If it won't start in a couple of tries then WAIT at LEAST 1 hour before attempting to start the bike again - this often allows a restart which might get you home.
Total HES failure will eventually occur if the bike is continued to be used without replacing the HES.
Ced.

R1100RT 1996.
Sent by Boson Quantum Transmission from the Starship 'Galahad'.
http://www.researchgate.net/publication ... ing_bosons" - It works!

User avatar
Dawntreader27
Forum User
Posts: 23
Joined: Sat Nov 25, 2017 12:52 pm
Country of Residence: UK

Re: R1100RT surge/snatch when riding above 3000rpm

Postby Dawntreader27 » Tue Jun 19, 2018 11:58 pm

Hi everyone and thanks for coming thru' with some very helpful suggestions.
I will start working thru' them and post when I find exactly what it is that's causing this.
Cheers
Nik


Return to “Oilhead (R1100/1150/Cruiser) Q&A's”

Who is online

Users browsing this forum: Majestic-12 [Bot] and 18 guests