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Silage
17th February 2005, 19:38
The GS now has over 3600km and I am being a bit more adventurous. I have only tried the following in 2nd (130+km/hr) but suspect it is the same in any gear. The revs rise smoothly up to about 9000/9500 (red line 10,500) then at the same point each time it feels like it is missing and the tacho jumps around between about 9k and 10.5k rpm. It stays at that speed and won't go any faster. Suggestions :spudwhat: :spudwhat:

1) electrical fault
2) rev limiter set too low (the 180km/hr limiter has been removed)
3) off tune (prob not)
4) summit else??

Cheers

Blakamin
17th February 2005, 20:03
you are passed the useable HP and its trying to valve bounce???
seriously, I'd have the limiter checked....
or the coil(s)

James Deuce
17th February 2005, 20:10
On my old TRX you had to short two connections on the CDI to remove the 180km/hr speed limit. Get it wrong and you were limited to 7000rpm in all gears as the speed was governed by a top gear rev limiter. Tampering with it and getting it wrong set the rev limit to 7000rpm in every gear. Check with whoever did the job, after you've researched the correct limiter removal procedure, that they followed the procedure exactly. If not they can buy you a new CDI.

dss3
17th February 2005, 20:53
sounds very similar to symtoms my TL was showing this week, with the addition of my bike feeling like it had less power. The problem: lobe snapped off inlet camshaft, hope your luck is better than mine!!

_daryl

Silage
18th February 2005, 21:20
sounds very similar to symtoms my TL was showing this week, with the addition of my bike feeling like it had less power. The problem: lobe snapped off inlet camshaft, hope your luck is better than mine!!

_daryl

Hey Daryl
Yikes. How many Ks has the TL done?

dss3
18th February 2005, 21:34
60k...

_ds

Silage
19th February 2005, 20:19
Talked to another GS1200 rider today at the Rakaia gorge (he from Timaru - thanks man if you are a KBer) and he indicated that it was the rev limiter cutting in at just before the red line. They all do it. Can any other GS1200 rider confirm this?

Also, he had a natty way to see what speed the GS is doing after it passes 180 - fit a treddly speedo/computer thingy. He had one that reads up to 300km/hr (not that it would be necessary to go that far of course) and stores max speed etc. Stay below 180 may be another.

TwoSeven
19th February 2005, 21:42
Many bikes shut down a couple of cylinders (usually the middle two) after peak power for heat reasons - also few bikes actually rev to redline - its really there for over-run for people who cant change gears.

When a limiter kicks in it just chops a spark or two causing the revs to drop, then pick up gain as the limiter kicks out. The effect is a bit of surging.

Not sure about your particular machine tho - not being a honda it probably needs to be pushed backwards for a few hundred meteres to rewind the go faster springs :banana:

FROSTY
22nd February 2005, 22:33
Itd be interesting fitting the speedo unit off of a gsxr1100 g or even H onto your bike. Methinks a lot of ya problems would dissapear.
Ie I think theres diods in the 1200 gs speedo

Jantar
22nd February 2005, 23:11
The GS 1200 SS is rev limited to 11000 RPM in 1st and 2nd. The limiter actually starts to cut in around 1000 rpm before so that 11000 rpm cannot be exceeded. It is also limited to 180 kph in any gear. There is a mod to remove this speed limiter, but talking to different mechanics I have been told different ways of disabling it. Until I actually see a wiring diagram I'm not prepared to try any of them.

Silage
23rd February 2005, 12:08
The GS 1200 SS is rev limited to 11000 RPM in 1st and 2nd. The limiter actually starts to cut in around 1000 rpm before so that 11000 rpm cannot be exceeded. It is also limited to 180 kph in any gear. There is a mod to remove this speed limiter, but talking to different mechanics I have been told different ways of disabling it. Until I actually see a wiring diagram I'm not prepared to try any of them.

It would seem that removing the speed limiter is not a big deal - I bought the bike (new) in Ashburton and the shop there had removed it. I think there is a previous thread that explains a bit about remoiving the speed limiter ("attach a 3.5uf round thing to the red wire coming out of the 692 ohm ceramic resistor..." kinda thing). Yes it would be good to see a wiring diagram.

Thanks for the comments one and all. It looks like I won't have to replace the magneto. :banana:

TwoSeven
23rd February 2005, 12:47
Speed limiters are often done in the speedo and are mostley pretty simple to remove (its often just a pin that makes a contact when the needle hits it).

Rev limiters can sometimes be bypassed by joining a couple of wires at the cdi or by adding a special unit that converts the signal inline to the cdi. But you really probably dont want to modify the rev limiter.

Usually there are design constraints in the engine giving a reason why they dont want it that high, also most engines produce peak power and torque well below that limit, so there is no reason you should be up that high - it just means in-effective use of the gearing (unless in 6th).

Jantar
23rd February 2005, 20:15
Speed limiters are often done in the speedo and are mostley pretty simple to remove (its often just a pin that makes a contact when the needle hits it).... .

Sometimes correct. But the GS1200 doesn't have a speedo needle. Its all electronic.

craigs288
27th March 2006, 08:38
Just joined the forum because I am looking for info about my bike, but now I want to ask some questions about this limiter.

Bought my bike with a thousand km's on the clock from a guy in Rangiora at the start of march.

Can anyone point to the thread that descibes what actions to perform inside the speedo, or will I have more luck by ringing a bike shop.

9000rpm in 3rd = 180km/h and it won't go any faster in 4th or 5th. Not that I do this often but it would be nice to know I could exceed this. So if I go to a track I don't want to find myself orbiting at 180km/h.

I was also hoping to find out what sort of specs the camshaft has. More along the lines of opening and closing angles of inlet/exhaust valves.

Richard
4th November 2008, 16:39
Hi
This is an old thread but no one has actually posted here how you actually preform the Speed Limiter Removal.
I need to do this on my 2004 GS1200SS.
So come on...fess up....how's it done ?
There must be some bike shop mechanic that knows how to do it. I do all my own work so I'm not going to take it to any shop. Anyway there cant be many of the GS1200SS left that need it doing so you will not be losing any money by telling me.
PM me if you don't want it on the public forum.
Worst case....where can I get a wiring diagram for the Jap model GS1200SS
Looking forward to any help I can get.
Thanks
Richard