has anyone seen this link before?
https://www.youtube.com/watch?v=SYnnU2Fg3Z8

appart from instant power and thrust, what other effects would it have on a K?
does it really need it?

No it doesn't need it, no one ever needs that much horsepower but it sure is fun.

I just purchased a turbo K100. It has the 4 injector kit. Boost is around 8psi now, judging from the boost guage. The power comes on smoothly as in a 2 stroke triple. It really just seems to get angrier as the RPM climbs. I have only put on 20 miles since buying it. I will give more reports this spring. Previous bikes include H1 kawasaki 500, FZR1000 yamaha, TL1000S suzuki, Buell 1200 Cyclone M2, R90, VF500 Magna, GL1500 Goldwing, Norton Commando (Dunstall), KLR650, RM250X, KX250, TTR225, CB900, BSA 650, H3, A7SS, S90, Maico 450, Triumph 250, 1985 GPZ900, am I rambling?
Art

ARTCOLLINSJR wrote:I just purchased a turbo K100. It has the 4 injector kit. ...., am I rambling?
Art

Not really... I would if I had one

BTW good luck. My guess is that u will do a full service and take it easy until you had a few hundred miles experience with her? then open the taps and see how she moves

My turbo cars (SAAB ) were 1atmo or about 15psi .This is mild boost and really just a torque enhancer , nice to have with the hills round here, actually really nice !
8psi on a K ? Don't know.... but gut tells me any gains may be due to the injectors .

A tech friend worked with Matt Capri for a while before the clash of Giant Egos led to the parting of ways. He still has a turbo K-1. 8 psi boost is pretty mild but consider this is on stock pistons. Most turbo cars use low compression (6:1 or so) pistons and make power off the turbo. Some of those record setting turbo race bikes had very trick Venolia pistons with offset pins and lower compression to take high boost pressures.

Beware you can chew through drive line components at an alarming and expensive rate if you choose to turbocharge. The engines are grossly understressed in stock form, but not so much the drive line. The turbo race bikes had custom transmission components to take the stress, and trick three petal ceramic clutches. Oh, and spinning a K bike engine up to ten grand can be life threatening, not because weakness in the engine but because the alternator will detonate like a bomb. I know three people who have seen K bikes imbed parts in dyno room walls when spun to five digit rpms, and every time it was the alternator that let go. One of Matt Capris race bikes had to have custom gearing in the intermediate housing to reduce the speed of the alternator. They don't call him "Matt Debris" in Southern California for no reason!

Here is the skinny on turbocharging K bikes.

[url=http://www.rbracing-rsr.com/bmwturbos.htm]http://www.rbracing-rsr.com/bmwturbos.htm[/url]

Ghost who rides wrote:My turbo cars (SAAB ) were 1atmo or about 15psi .This is mild boost and really just a torque enhancer , nice to have with the hills round here, actually really nice !
8psi on a K ? Don't know.... but gut tells me any gains may be due to the injectors .

Hmmm... off the top of my head..

The piston efficiency in sucking air into cylinders at high revs is probably about 80% ... so turbo would simply correct that. I thought that 8psi is a bit low, but 15 psi is just 1 atmosphere, 8 psi is 0.5 atmosphere. Logically any pressure above 1 atmosphere pressure should "correct" and eliminate the 20% "loss" and maintain the fuel/air ratio as it should be at higher revs. Having said all of that it all depends on the fuel mapping allowed by the K100 designers, who I suspect, would have accounted for the air flow inefficiencies of the naturally aspired engines.

Maybe an experiment is in order... up the pressure by small increments and take it for a spirited ride. Keep an eye on the temperature as well as performance. Else, measure air/fuel ratio, but that is nowhere as much fun

Going from 8psi to 18 psi in my 1.8L Turbo Audi A4 went from 120 HP to 190 Hp
(APR tuning remap), so from this , and the seat of my pants , I would put the 987 cc engine boosted 8 psi up from 90 HP to 120 HP
1800*10=18000/70=257.4
987*8=7896/257.4=30.67
If I can get to a dyno, I will post real numbers.
I can't wait to play with the boost control/wastegate

Anyone wants to experiment with the 8 injector competition turbo setup? It uses 8 injectors and has a plenum to replace the air box. I have one for sale. It is just like the one on the RB racing website. It was sold by Matt Capri back in the late 80s and early 90s. I was going to turbo my 1985 RS but plans change. If anyone wants more info contact me.

ARTCOLLINSJR wrote:Going from 8psi to 18 psi in my 1.8L Turbo Audi A4 went from 120 HP to 190 Hp
(APR tuning remap), so from this , and the seat of my pants , I would put the 987 cc engine boosted 8 psi up from 90 HP to 120 HP
1800*10=18000/70=257.4
987*8=7896/257.4=30.67
If I can get to a dyno, I will post real numbers.
I can't wait to play with the boost control/wastegate

Nice...

Your Audi is a recent model, and mapping to account for extra air, has been remapped. I wonder how this is done for 1985 K100 where the injector timing/fuel quantity is controlled by electronics (almost hard wired). How do u remap that?
Of cources is the turbo controller has replaced K100 system remapping will be reasonably easy.

L-Jetronic is an analog system and can be adjusted in two ways. You can change the spring pressure on the vane in the airflow meter and you can change the positon of the potentiometer relative to the vane which changes the relationship between pulse width and vane position. I am betting that with a turbo set up you want to increase spring pressure on the vane so the turbo doesn't just blow it full open.

You can also go with the eight injector set up and fool with the two adjustments mentioned. You don't really need to dump L-Jet for a digital system. There are automotive websited devoted to L-Jet that explain the dark arts of adjusting it. It really isn't as scary as it sounds, it just requires some patience and attention to detail. You need the same when mapping a digital system.

Themason wrote:L-Jetronic is an analog system and can be adjusted in two ways. You can change the spring pressure on the vane in the airflow meter and you can change the positon of the potentiometer relative to the vane which changes the relationship between pulse width and vane position. I am betting that with a turbo set up you want to increase spring pressure on the vane so the turbo doesn't just blow it full open.

You can also go with the eight injector set up and fool with the two adjustments mentioned. You don't really need to dump L-Jet for a digital system. There are automotive websited devoted to L-Jet that explain the dark arts of adjusting it. It really isn't as scary as it sounds, it just requires some patience and attention to detail. You need the same when mapping a digital system.

Thanks, I just thought of another way of introducing more fuel... higher pump pressure and higher capacity injectors.
Anyway, I love to hear how you get on with that

http://cgi.ebay.com/ebaymotors/1985-k-100-rs-bmw-/161081405623?pt=US_motorcycles&hash=item25813330b7

FWIW...