MORE POWER!!!!!!!

mark2jag

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Just really thinking out loud,so perhaps i should stop doing so. How much power is attainable from a reasonably standard 1200 gs engine. I'm talking about changing such things as the standard cam, BUT i'm not talking about that HUGELY expensive Turbo kit I saw on here sometime in the recent past.... 1200CC and just 110/115 BHP doesnt really seem a lot. I know power isnt everything theres also torque, but I'm entirely curious. can you lot fix it for me to have an accurate ish guess at what it may handle before going south in probably quite a big sudden and dangerous way..



Fank y' all

Mark


P.S. OR is the limiting factor in all this the shaft drive, and would that stop you putting too much in the way of power to it..
 
Go look at a HP2 Sport engine, to get your current base line of what might be not too possible without too much difficulty, whilst retain some sort of day-to-day easy rideabilty.
 
It'll be a very expensive way to achive not very much. That's fine if the tuning exercise is pleasure enough but if you want a more powerful bike then you really need to sell the GS and buy something else.

There are a lot of limiting factors, the most fundamental is the airflow, and unless you do put a turbo on it, then you'll not get a lot more air through the engine without going for a highly resonant intake and exhaust which will screw up low rpm driveability.

If you can get more air through the engine a PowerCommander or remap will give the necesary fuelling. You then have the resulting heat to get rid of.

Its not a coincidence that all other engines producing upwards of 100bhp are watercoled, and making watercooled barrels and heads is beyond most of us.

If all that can be overcome then you have a driveline, brakes & suspension designed for 110bhp suddenly dealing with more (or failing to deal with more).

Years ago I read a magazine article where the writer that said that whenever he wanted a faster bike he considered how fast the racers of the day would be able to go on his current bike, and then applied a bit of concentration to closing the gap. Makes sense to me.....
 
Often wondered what a GS would be like with an engine from a R1200S ?

Power: 122.00 HP (89.1 kW)) @ 8250 RPM
Torque: 112.00 Nm (11.4 kgf-m or 82.6 ft.lbs) @ 6800 RPM



TK.
 
I would go with trying to better the power to weight ratio. Std can/cat is ridiculously heavy, try and get a titanium version and y piece. Filter and power commander should smooth out the delivery and ensure an efficient burn. But in my opinion it defeats the object somewhat, the bike (latest 1200 anyway) goes, stops and handles way better than it should and you can load it up if required for the longer jaunts. Half the fun is closing down badly ridden sportsbikes on the twisty bits whilst carrying your weekend luggage and 12 cans of Theakstones in your panniers :D.
 
I think the 1200GS with 110bhp/110? Nm is extremely capable on "GS" roads. At least it is for me. That is any road on a Michelin map with a green line next to it, the alps etc. If you don't wear out a rear tyre in 4-5k mls on such roads, and don't have a profound V profile in the front, then you are not using the capabilities of this bike.
 
Perhaps I am too old but messing with stuff like this mostly ends in tears but i take your point about it being somewhat more than what it is!


Mark.

Your answer is to hang more and more bits off the bike, reducing its feeble power to weight ratio even further ;)
 
Your answer is to hang more and more bits off the bike, reducing its feeble power to weight ratio even further ;)

Its true! :thumb

In my yoof it all used to be about stripping unwanted tat or replacing parts with lighter or high performance parts.

Nowadays its just layering protective crap over the top of sub standard crap, making the bike resemble some sort of armadillo.
 
Arguably the best way to increase Power / weight ratio is to get fit! The average tosser is probably overweight, and likely quite lot are clinically obese.

Bet the average tosser would struggle with Cardio Vascular exercise.

So, throw your time and money on getting fit not speed-farkling yer bike.
 
Just really thinking out loud,so perhaps i should stop doing so. How much power is attainable from a reasonably standard 1200 gs engine. I'm talking about changing such things as the standard cam, .......... 1200CC and just 110/115 BHP doesnt really seem a lot. I know power isnt everything theres also torque, but I'm entirely curious. can you lot fix it for me to have an accurate ish guess at what it may handle before going south in probably quite a big sudden and dangerous way..

P.S. OR is the limiting factor in all this the shaft drive, and would that stop you putting too much in the way of power to it..

Figures from US models, which I assume are the same as the European variants.

HP2 Sport:

Max Power: 96 KW 130 hp @ 8750 rpm

Max Torque: 115 Nm 85 lb-ft @ 6000 rpm

Transmission / Drive: 6 Speed / shaft

Gear Ratios: 1st 2.176 2nd 1.625 3rd 1.296 4th 1.065 5th 0.939 6th 0.848

Top Speed: 248.7 km/h

Wet-Weight: 178 kg

====

By way of simple comparison, the 1200GSA is:

Max Power: 81 kW 110 hp @ 7750 rpm (20 hp down, delivered 1000 rpm lower)

Max Torque:120 Nm 88 lb-ft @ 6000 rpm (3 lb-ft up, at the same RPM)

Transmission / Drive: 6 Speed / shaft (Same)

Gear Ratios: 1st 2.375 2nd 1.696 3rd 1.296 4th 1.065 5th 0.939 6th 0.848 (I guess it wouldn't be difficult to alter the ratio of the first two gears to match)

Top Speed: 193.0 km/h (faaaaast, not)

Dry-Weight: 223 kg (so add oil and 33 litres of fuel :eek:) plus the obligatory ten ton Tosser, panniers stuffed full with root vegetables, full-on extra bling.... and the all important hedgehog in pocket, too :D..... Probably it's greatest limiting factor; that and shoving a brick through the air.....

Oh, and having to be steady on the throttle (variable rev limits) on the Sport whilst the engine comes up to working temperature, probably due to very tight tolerances...
 
Pah- ignore the above and have a go.

I have NO experience of improving the power/performance of GSs (other than suspension mods) but lots of experience tuning other bikes.
You don't have to get huge power increases to really feel an exciting improvement. 10% would be a lot more fun!
I would have thought you would get this through improving air flow without spending huge amounts of cash.

Consider the air intake/airbox- can the flow be improved.
More free-flowing air filter.
Take the heads off and dismantle them- use carbide bits to enlarge and smooth the porting (OK, maybe get somebody else to do this bit!)
More free-flowing exhaust.
And most importantly- some dyno time. You will probably need a power comander (or similar) at this point.

I'd be surprised if you didn't get 10% improvement.

Beyond that- cams, valves, pistons. No idea about the bottom end, clutch, shaft, etc. if you went down that route though.

The engine shouldn't run any hotter if it is set-up right. It will be burning fuel more efficiently and letting the hot gasses whizz right out!
 


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