Must go faster V

[Panzer Patrol]

I’m back again.

RS cams are in, RS air trunks fitted, weather bloody awful but still trying to road test the mods. So far, it’s proving really difficult to judge whether the bike is much better or not just through the seat of the pants approach, especially if it’s lashing down with rain and blowing a gale. I really need to try it out against my mate’s bikes. Other than saying the motor feels strong I can’t offer up any more feedback at the moment.

One thing I did try was faffing about with the catcode plug settings. I have always harboured a suspicion that the Motronic box contained mappings for all the models. It would make sense on BMW’s part to produce one chip for all models and just use the catcode plug to set them for whichever model.

With this in mind I legged it down to the local dealer showroom and hoisted off the seat on a new 1150RS and checked out the catcode plug. The RS uses a 3 prong plug. So back home make up a 3 spade jumper lead. Now… I have mucked about with a 2 spade jumper, but never a 3….should be fun.

Out on the road I fitted the 3 spade jumper, reset the Motronic and set off. Just pulled away as normal in 1st and 2nd then into 3rd and whacked the throttle wide open. The bike accelerated really hard then at 4000ish rpm the motor just stopped. It was like hitting a brick wall. I shot forward, banged me nuts off the tank and tried to head-butt the screen. Groan…something not right. Maybe too much throttle… could have over-choked it, try again. Nope…same affect, motor just cuts out at about 4000 rpm. No way will it run on the RS settings. Removed the jumper and ran it with none in, and the bike is back to normal.

Conclusion. Original theory of different mappings inside the motronic for different models is bollox. The mappings must be for different countries with either, different fuel grades or different emission laws. In effect they are specific chips for RS/RT , S, and GS. All the catcode plug does is set them up for different countries.

Anyone care to speculate?

 

[Henry]

A while ago I put the code plug setting in a table for the Dutch GS club. As you can see there is only one pin unused on all GS versions (pin 85)

http://www.bmwgsclub.nl/oud/techniek/plugtabel.html

But all the R1150 range use the SAME motronic,
All p/n 1361 7667 285. you can't get the Eprom separately

I have checked it for the R,GS,RT and RS

 

[Panzer Patrol]

Brilliant!

Many thanks Henry. Will investigate further and keep you all posted.

 

[Panzer Patrol]

Henry,

Checked out your web site and it looks fascinating and I am dying to read it. One problem.... its all Dutch. Is there an English translation anywhere. I am a Geordie, English is my second language, but I should manage. God! I feel so ignorant

Many thanks

 

[Finbarr]

This has got me salivating...

Panzer!
Your dedication to the pursuit of more power is commendable.

I've just picked up a brand-new twinspark GS, and am running this in HARD! Once the oil is warm and the engine up to temp, it gets ridden very hard. I changed the oil at 25 miles and was amazed at the gunk that was in it. I expected some engine swarf but not the amount of aluminium powder that was mixed in with the oil (which had turned black with a kind of silvery sheen).

Now at 150 miles (got the bike yesterday) and the oil is still clear. I'm convinced you can extend engine life considerably with this first very early oil change. But I'm waffling - on to the "more power" bits...

After first service I'm doing the remus & K&N bit and permanantly sending the cat off to the vets. I'm also very intersted in the RS trunk replacement and the RS cams that you've done.

This is more from the point of view of getting a more usable 6th gear, and improving the mid-range.

I was wondering if you could elaborate a little on any tips/tricks you determined on fitting the RS parts? Was it really as simple as unbolt 1 and bolt-on 2?

I'm also very keen to see how you get on with the cat codes for the motronic.

This has been a great thread and I'm gagging to read your next installment!

Kind regards,
Finbarr

 

[Malky]

Anyone care to speculate?

"The R1100RS/GS series has six (6) different maps available in the later series control units to "custom tailor" parameters to meet emission/country-specific specs. No less than five (5) cat code plugs are specified for R1100RS/GS configurations! Each one is distinctly different in emissions, performance, and drivability. "
for more see this

 

[Panzer Patrol]

Malky - top man! Thanks for that. More study required by yours truly.

Finbarr - If you are at all handy with a set of spanners its a piece of...cake. All the info is in the GS manual on CD. The one thing I would recommend is the crankshaft locking tool. Its called a spigot or sumthin. When the engine is on the TDC marks, you just shove it through the hole above the starter motor. You can then cheerfully heave away at things like camshaft sprocket bolts (which are tight) without fear of moving the engine.

It is quite simply an unbolt and swap process. Being careful, taking your time, its an afternoons work swapping the cams. Also may be worth ensuring that you have some socket drive allen keys and a torque wrench.

The only dodge when putting on the RS inlet trunks is... shove the GS ones inside the air box. Push the rubber grommet inside the air box, then... turn and pull the whole lot out (the suckers are some length).

Fitting the RS ones....remove the injectors, shove the RS trunks inside the airbox. Refit injectors, then....pull out the trunks and fit to injectors. Remember to balance the throttle bodies after disturbing them.

PS: I hope to swap the motronic off my mates bike which has a BBPower chip in it... keep you all posted

 

[Henry]

Henry,
Checked out your web site and it looks fascinating and I am dying to read it. One problem.... its all Dutch. Is there an English translation anywhere. I am a Geordie, English is my second language, but I should manage. God! I feel so ignorant
Many thanks

Panzer,
I can translate the table if you want,
the motronic/abs readout procedure is a bit more work...

But I put you in holding for a few day's

Been busy with my 21" conversion, 200km test-drive tomorrow in dirt

Ill post you guys about the conversion when all is tested

 

[Panzer Patrol]

Wow, nice looking piece of kit you've got there.

Thanks for the offer of a translation but, as someone pointed out at work, one of our new staff is from the Netherlands so I am going to ask him. (or bribe him with my spare flat screen for his PC)

Thanks again

 

[Finbarr]

This is getting a little confusing...

Panzer,

Cheers for the advice - I got the manual on CD the other day, it's the year 2000 model and doesn't cover the servo brakes or twinspark gubbins on the 03 model, but I'm sure it's perfectly fine for the purposes of cam replacement and trunk swapping.

However! The link described in Malky's post has an article which describes how an RS owner obtained better power delivery and improved performance by fitting GS trunks!

This article was dated '97 so I guess some things may have changed, but I have to say, as a newbie to all this horizontal twin business, I'm a tad confused...

Do you know of any pages that describe the evolution of the engine that might explain why in 97 swapping GS trunks onto an RS improved things and why today the opposite is true? Are there any articles that you read or know of that you could point me at which stimulated you along your current line of thinking?

I'm not questioning your method or results here - I'm just curious to understand the process, and for the cheapness and simplicity of it, I'm keen to give it a whirl myself!

cheers,
Finbarr.

 

[Panzer Patrol]

Hi Finbarr,

You have every right to question my findings so far....and you are right it doesnt make sense. Seat of the pants aint a very scientific method at all. I think...stress think, that this mod on the RS gave low to mid range torque increase (nice for touring). Because I tend to swing on the throttle, I may be experiencing mid to top level increase in torque. (nice for being a prat and getting on everyones nerves).

The article Malky pointed me at was for the 1100 engine on the 2.2 Motronic. We have 1150s with 2.4 Motronic, so I am not sure if this article applies to us. Needs more investigation.

Until I can drag my softee mates of their sofas and try our bikes side by side it may be prudent to take my findings with a pinch of salt. Needless to say I am happy with the way the bike goes, so I must be doing something right.

Keep the faith

 

[Duncan R]

Going Faster!!

Panzer,

Great thread - been watching what you're doing with great interest - keep us posted!

The inlet trunks differences do make sense (in a strange way) - If you ride a GS and RS back to back, or see stock dyno charts for each (some great ones on an Aussie BMW perfomance centre - I'll dig out the links if anyone wants it) you can see that both engines are basically similar, but that the GS makes better torque low down the rev range (and max torque too) but less top end power, whilst the power curve on the RS is rocked the other way. So the RS makes less low down torque and power, but better mid-top end power.

Lenghtening an engine's inlet manifold (air trunks) tends to move the power & torque down the rev range, as does increasing the tuned length of the exhaust. Shortening does the opposite. This is due to the pressure waves travelling back and forth in the inlet / exhaust systems arriving back at the inlet / exhaust valves at different times depending on the lengths involved. These pulses are travelling at the speed of sound, and are sperate to the gas movements in the inlet / exhausts.

You get similar effects by increasing or decreasing the internal diameter of the inlets / exhausts, but this is because a smaller dia pipe flows gas faster/better at lower throttle/revs than a larger dia one. Thumb over the end of the garden hose principle.

However for it all to work in harmony you need to optimse both effects with the cam timing as well - so no point putting hairy great cams in an engine with long inlets / exhausts and small valve sizes - you'll get a truly nasty power delivery!

Panzer, have you looked at gasflowing the heads and increasing the compression ratio? Also the Laser exhaust looks to be giving v.good results on the R1150R. You may find you get the best of both worlds once you have done those mods too.

Lets see the dyno charts as soon as you have them!
Best of luck, Duncan R.

 

[Isaac Hunt]

panzer

lissen to the man - he noes wot hes talking about
i lissened but didnt unnerstand
my m8 says you need high compreshon rings to make it go faster

 

[Panzer Patrol]

Im listening...I,m thinking...my brain now hurts.....lying down now.
Cheers guys...keep em coming

 

[Finbarr]

Duncan,
Thank you, great explanation - it all falls into place now!

I'd love to improve the mid-range and get a usable 6th, but I'm not sure I'd like it to be at the expense of the low end torque, which makes me quietly smile everytime I pull away from the lights...

Still, I quess the old saying about 'eating cake' is relevant here.

Kind regards,
Finbarr.

PS: Panzer, hope the headace goes away so you can do some more testing!

 

[Panzer Patrol]

Been for an extended test today from Durham to the Edinburgh bike show. The weather and roads were awful and the high winds meant it was like wrestling an octopus all the way there and all the way back...sheesh.... I'm completely spanered.

But, the main bit I wanted to say was, bottom end grunt and drivability are all still there. It pulls from nowt and keeps going. As low as 1500 rpm and away it goes. MPG seems just the same as well.

Took the baffle out of the Remus revolution and it seems quieter...nothing makes sense with this bloody bike, its arse about face every time I do summit. The main reason I did this was because of Duncans well reasoned argument that "big holes are best". So the can now has a ginormous hole in it. It should come as no suprise to everyone, but.... it revs better. Daftest thing is....no loss of bottom end. This bikes gonna have me in the nuthouse before I'm done.

Keep the faith