1150GS dyno results

[guzzimag]

Hi Folks - I mentioned several weeks back that I'd get my bike on the dyno and have. For anyone interested it's an 02 1150GS, with a Remus y piece and carbon Revolution can, with the "steptoe" CCP mod done.

Dyno run was done at Hobbsport Racing ooop north, they have a fairly conservative dyno in terms of HP reading. Results:

74.9bhp at 6400rpm
77ft/lb at 4250rpm

As any fule know torque is what we want so that's healthy enough for me. The torque curve is pretty flat (good) right through the range it's making 65ft/lb at 2400rpm. Some pretty good stump pulling ability.

Fuel/air ratio - it's slightly lean everywhere, no surprise, but not to the point it's going to cause problems like holed pistons. At 85mph in top fuel/air is spot on it's at the lower revs where it's most lean.

£580 for a Power Commander and setup - is it really worth it?? Anyone spent the money, what did you think of the results?

cheers

Magnus

 

[Colban]

Hi,is "fairly conservative" their term for the dyno to be inaccurate.
Under 75 BHP is a big drop from the factory claim of 85 BHP.
BWMs HP claims are usually more accurate and reliable than most so i'm surpised to see a big difference.
With the mods you've done i would expect to see 85 at least.
Did you set up the motor before the run?.New plugs/air filter,TPS calibration,TB balance,valve clearances/end float and maybe ignition timing check.What RON fuel did you use ;95 or 98?.

 

[guzzimag]

Bike is in fine fettle and just given a service, tps reset balance and standard 95ron unleaded. I also have a factory claimed 85bhp guzzi that makes 67

Maybe Hobbsports dyno could be described as inaccurate yes. Certainly feels like a healthy motor when I open the taps though. I'm never convinced by any manufacturers bhp claims, BMW or not.

 

[Greg Masters]

Power figures on a rolling road dyno are pretty much a waste of time. Put the same bike on the same dyno next week and you may get a different readings.

To get a truly accurate power figure, firstly you have to have an accurate dynomometer. Then you have to adjust for all manner of things like air temperature; air pressure; humidity and a whole host of other things.

Very few do this.

Greg

 

[ukaloon]

I'd have thought that the 85bhp claim made by BMW would be taken at the crank, as with most manufacturers. Allowing for 15% loss in powertrain anything over 75bhp at the wheel would be good. The dyno's I've used adjust for altitude, humidity etc.
At the end of the day it's only an indicator, and better used as a before and after.

 

[Greg Masters]

At the end of the day it's only an indicator, and better used as a before and after.

My point exactly! (Except you said it in fewer words!!)



Greg

 

[tinker-27]

i run a dyno for a living and they are not that inacurate i can run a bike a year latter and it will put out the same reading if its the same power ,true you do have to put in some settings but they are know,most people use dynojet dynos which are very accurate mine is within .5 bhp to PDQs dyno and steve burns dyno with the same bike .the thing that people dont think about is the simple stuff like tyre presures ,and 1150gs drop power badly on a dyno if they get even a bit hot you need to keep them cool you can loose 2bhp per run if you do rur on run with out cooling the motor as most dynos dont cater for the cylinders and the cooling fans are not in the air from the fans.a dyno is only a measuring tool but they are very accurate if used correctly , that power does not sound great but how hot was it i find that you only get two power runs at a time once warmed up ,i would have thought it would be into the 80s even at the wheel i have a 1150gs in the 90s (just) with std internals only induction and exhaust mods and my mates (remus+y+techlusion) is about 85bhp,i dont think the power comanders are worth it on a gs,the twin sparks do run weaker that the single sparks but power is the same

 

[Steptoe]

i run a dyno for a living and they are not that inacurate i can run a bike a year latter and it will put out the same reading if its the same power ,true you do have to put in some settings but they are know,most people use dynojet dynos which are very accurate mine is within .5 bhp to PDQs dyno and steve burns dyno with the same bike .the thing that people dont think about is the simple stuff like tyre presures ,and 1150gs drop power badly on a dyno if they get even a bit hot you need to keep them cool you can loose 2bhp per run if you do rur on run with out cooling the motor as most dynos dont cater for the cylinders and the cooling fans are not in the air from the fans.a dyno is only a measuring tool but they are very accurate if used correctly , that power does not sound great but how hot was it i find that you only get two power runs at a time once warmed up ,i would have thought it would be into the 80s even at the wheel i have a 1150gs in the 90s (just) with std internals only induction and exhaust mods and my mates (remus+y+techlusion) is about 85bhp,i dont think the power comanders are worth it on a gs,the twin sparks do run weaker that the single sparks but power is the same

Well i'm glad thats cleared that up.

 

[guzzimag]

I was more concerned about it running too lean than anything else, and it isn't so I'm happy. Spent the weekend in Scotland, two up, full luggage, tank bag, tent, kitchen sink, etc and it still pulled like a train. Never ridden anything so competent, I love it

 

[Jon P]

Over the last couple of decades maybe things have changed with BMW. When the first 1100GS came in 1994 out it was rated at 80hp and if my memory serves me all the magazine tests at that time were getting results of about 85hp at the wheel! I bought my first 1100 from the first batch into the UK (all my mated teased me - ugly duckling etc.......not me, the bike!) but I loved it, I then bought one of the last 1100Gss in 1999 and it was definately down on performace. I then had an 04 1150 which felt no better than the last '99 1100 and have just bought a new 1200GSA which, again does not feel to have a 100hp when compared with the others!

My own thought is that over that period of time emissions have got ever tighter - this leads to the capacity increase every few years (and of course BMW need a reason for us to change the bikes!) and of course these tighter emissions create the ever eroding power losses that we seem to see.

My first GS - in 1991 was a lovey red 800 rated at 50hp - and when ever tested the 800s would give almost 50hp, again measured at the rear wheel. I also had a 1993 100GSPD which was put on a dyno and developed 57hp at the wheel (quoted power was 60). It seems that the latest 1200s only produce about 80hp at the wheel when they are quoted at 100hp - 20hp loss is too much for the transmission.

I do remember someone years ago telling me that BMW always quoted power at the wheel and not the crank and this explained why their respective power sometimes looked a little low for a given engine capacity when compared with other manufacturers - BUT it was considered the honest approach. I do know that some of the manufacturers a few years ago would not only quote crank power but would also remove every other load including generator, water pump etc.

BUT, does the specific number really have any value ather than idle curiosity?

 

[davegs]

Vincents BHP

The vincent rapide ,not exactly slow in it's time knocked out (factory figures) 45 bhp and the black shadow 55 bhp. on 7-1 pistons (shadow ) and 70 octane pool petrol.
Dave ( rapidely getting uesd to GS's) gs. ( must wash out my mouth at once)

 

[Bigtwin]

My own thought is that over that period of time emissions have got ever tighter - this leads to the capacity increase every few years (and of course BMW need a reason for us to change the bikes!) and of course these tighter emissions create the ever eroding power losses that we seem to see.

That must be right - and less powerfull cleaner fuel etc too, plus cats and all that add weight and sap power.

I remember when the exhaust fell of my Honda moped - blimey, you could wheelie it on the throttle!

 

[FBF]

add 5-10 psi in the rear and watch as your BHP rises 2-3 bhp. try it and be amazed

 

[Arthurwg]

Vincent Rapides were never fast. They just seemed fast because they were so difficult to ride.

 

[Paul Young]

74.9bhp at 6400rpm
77ft/lb at 4250rpm

The power figure certainly seems a bit low. With a standard EFi chip, Remus can & Y piece plus a K&N & 1100S inlets, I was getting 85bhp at 6800rpm. Mind you, I was only getting 70ft/lb at about 5600rpm.

£580 for a Power Commander and setup - is it really worth it?? Anyone spent the money, what did you think of the results?

I've a PC fitted, but it was done by Dynojet when they wanted to trial them & needed a GS to test one on. The difference wasn't huge in terms of peak figures...

87.79bhp at 6800rpm
72.94ft/lb at 5800rpm

...but the biggest improvements were to the "part-throttle" response with a 10% improvement in power/torque at a 40% throttle opening.

I wanted it set up for performance, but it is a doddle to set up different maps - for example, for touring (greater range?) - & switch between them via your laptop. It also allowed them to maintain, near-optimum, fuelling throughout the rev range. I'm very pleased with it, but then, it didn't cost me £580...

 

[Dunk]

I ended up buying a PC3 after fitting a Remus pipe and K&N as bike was running lean and I needed it a week later to go to France on. I don't think that it's worth the £350ish plus custom map, if you get that, all adds up. If the Steptoe thing works and your bike's not dangerously lean I'd be happy with that.

My bike only puts out a measured 81bhp (Remus Y + endcan, K&N, PC3) up from 77 with Y piece only.

It's a lot of money for little gain.

 

[Cookson]

I had a Power Commander fitted a year ago, it sorted out the fuelling problems right across the rev range & made the bike easier to ride around town, ie. no surges around 3,000 rpm no back firing & cleaner throttle response.

Figures on the Dyno :-

83.30 BHP @ 6,700 rpm
71.66 Torque @ 5,400 rpm

Cost me £500, expensive but worth it IMO, the bike is now a joy to ride & pulls like a train all the way.