I know the threads on this subject are old now, but  I am in the process of fitting 1100 tbs  to my k100 .

They have been on my bench for too long now... so its time to fit them

I swapped the throttle cable support brackets over to keep the original cable.  

Removed 14mm of cable outer sheathing to allow for full range of the throttle quadrant.

Swapped over number 4 butterfly shafts to use  original TPS.

Have used 1100 FPR but will check pressure when bike is running.

The rear breather hose was still fitted to all four bodies , so blanked off the return stub to the 1100 air box.

I will be using 1100 injectors off ebay after using cheapo injector cleaning kit .

Valves clearances will be checked too whilst waiting the Mr Postman.

So a couple of questions for the those who have done this mod..

1.  Will I have to adjust the mixture, as I will be using 1100 injectors,  and if so, do I use the adjuster located under the rubber plug in the air box, or the air flow potentiometer adjustment.


2. How many people have had to tweak the AFM vane spring for better throttle response .  

Bob

No need to use 1100 injectors as it will run too rich which cant be compensated for by tweaking the vane. The only big advantage of leaning it out with the vane is to make it run leaner in the top end with WOT where the L-Jetronic makes it rich for the protection of the engine.
TWB has tried to run the 1100 injectors and found the std 100 were best.

Hi- Im currently doing the same thing. I've already purchased new injectors but did alot of research beforehand. It seemed that some people had good luck with higher flow injectors and some didnt. I got the 4 hole style with a slightly higher flow rate.

Thanks for that Rick  I will stay with the standard injectors then.

Bob

Don't forget to advance the timing by 6 degrees (4mm if measured on the HE mounting disc). The two together give you a lot more kick for next to nothing.

Thanks Dai.

I tweeked the timing a little while ago and found it better at low revs.

Just waiting for new injector o rings and air box clamps to arrive and  see how she responds 

cant wait...

My set of 1100 tbs came with the blue marks still on the adjusters and all the bypass screws set as if they have come straight off the bench so hopefully they will reflect that when I hook up my balance tubes.

Then get my new front bt 045 fitted and happy days.

Need to get a spare brick sometime... no fun only having one when there is maintenance to do..

Someone on this forum did a really nice naked k100 .  Had  a blue and white tank I think..

Bob

Unless you've done everything you possibly can to lean it to within an inch of its life, like ripping out the airbox (not easy on an 8V K) and truly opening up the exhaust, there's no reason to use the 150cc K11 injectors just because you're changing to K11 TBs on an 8V K100 with 133cc injectors. They're plenty for the task. With the bigger flow it runs and idles flatter, chews more juice, and generally doesn't feel as 'peppy' down the road. Oh, and the accumulated soot at the end of the tailpipe will get annoying after a while. But try it for yourself.

Well.  that was an interesting day.

Got the back together and she started fairly quickly and seemed to be running very evenly.  

If I had only looked up I would have seen a dirty black cloud heading my way.

A quick resume.

Running 100 tbs, 

very smooth , balanced at tick over and beyond, checked twice in 6 months and very happy..

Bit of a missfire around 3k but clear after that. need to test hall sensors perhaps

Plug number 1 running slightly lean, others ok.

Air filter ok 

1100 tb swapped .

1100 fpr used

Old 100 injectors used with new seals top and bottom

Bike started well  but cylinders well out of balance at idle and above.

Could not balance at idle..although idle steady at 1k

Tps sensor set so first switch not used, continuity achieved on second stage near to full throttle so happy with that.

Tps disconnected during balance attempt

Pulled plugs to find all were running  very rich. 

 Coolant temp sensor is brand new too.

Question 

1. As Bert (crazy frog ) stated, the 100 and 1100 fpr pressure is the same , so unless I have a faulty fpr and the injectors are getting excessive pressure  how is my bike now running rich. 

Only the tbs and fpr were changed.

Bob

I thought that FPRs are different for LE-Jetronic and Motronic system - for K100 and for K1100 respectively. 2.5 vs 3 bar? Or am I wrong? 
Basically I plan to install K11TB to K100 soon, so I'm beginning to be curious )

They are the same at 2.5 bar. Where the confusion arises is that the volumes are stated at 2.5 for the K100 2V injectors and later on they started stating flow rates for all injectors at 3 bar for standardization so the K1100 injectors were stated at 3 bar but the system pressure is 2.5bar. However you cant just do a direct comparison when fluid mechanics come into the calculation and the K1100 do run just a bit richer but not 20% more as some expect.

Ok, I see. So, I'd like to do the same -> install K11 TB into 8V brick. Right now without any other modifications. Is it necessary to adjust MAF anyhow? I thought that vane flow meter will do its job and it will measure correct amount of air even with K11 TB? Or not?

Due to problems with mixture and balance with my 1100tbs, I have decided to have my 100 injectors professionally cleaned and flow tested. 3 day turnaround so not too bad.

My bypass screw o rings need replacing, where do I get these from?

Motorworks and Motobins do not list them.

fuel pressure, valve clearances and compressions to be checked.

I will invest in a cheapish  exhaust gas analyser to set the mixture.

I could get cylinders 2 and 3 to balance, but number 1 was higher  and number 4 showed a low reading and would barely   respond to bypass screw changes, hence the need to check everything.

I remembered to check number 4 butterfly shaft seal was in place when I swapped them over., and the plastic end cap is place on number 1 . I even put a little sealant on the TPS sensor body .

All bypass screw on my 100 tbs responded really well.

All good fun ... note to self,, you may enjoy doing maintenance , BUT GET A SPARE BRICK TO RIDE.....

bob

audibob wrote:My bypass screw o rings need replacing, where do I get these from?

This should be a standard metric o-ring. An industrial supply house should be able to supply you 4. Take the needle valve with you to get the correct size.

audibob wrote:I could get cylinders 2 and 3 to balance, but number 1 was higher  and number 4 showed a low reading and would barely   respond to bypass screw changes, hence the need to check everything.

I remembered to check number 4 butterfly shaft seal was in place when I swapped them over., and the plastic end cap is place on number 1 . I even put a little sealant on the TPS sensor body .

Did you swap out the #4 TB butterfly and shaft to accommodate the TPS? If so, the length of the k100 shaft is slightly longer than the K1100 shaft and you will need to add a spacer between the TB body and circlip along with the appropriate O-rings.

I am a little confused over adjustments to the mixture .

I am buying an analyser, so do I use the adjustment screw in the top of the maf together with the analyser.

Themason speaks about having to adjust the afm potentiometer setting to alter the mixture.

Some clarification needed please.

bob

Hi robmack,

Yes I did swap number 4 butterfly shafts .

I did make sure the threaded end seal was in place, but wrongly assumed the TPS would seal the air from the other end.

I need to remove the tps unit and check .

This would account the number 4 tb not reacting well to bypass adjustments

Because my 1100 tbs still show the blue paint marks intact, I am reluctant to make any adjustments until everything else has been eliminated.

Injectors are being checked tomorrow. 

Compressions are 150 on all four on hot engine and wot 

When balancing my 100tbs , number 4 balanced perfectly  at idle, but when checking at 5k revs, number 4 tool a little longer to meet up with the other three. 

Valve clearances check tomorrow even though compressions are even 

Thanks robmack

Bob

Removed the 1100 tbs today and  found, as robmack suggested , there was play between no 4 tb butterly shaft circlip, and the washer in front of the seal.

The seal was in place on the threaded end of the shaft.

I reduced the gap with a washer  just enough to exert pressure on the seal .

Replaced all bypass bypass screws and vacuum plugs .

I then blanked on side of each throttle in turn and blew down the other side and all four were sealed  correctly and air tight.

All bypass and vacuum orifices checked with carb cleaner and ok.

Checked all four butterly plates for gaps at closed throttle and found 2,3,4 showing a very small amount of light through at rest but no 1 showing nothing, so although my unit still has  the blue paint marks on the adjusters, balancing will need to be done.

This explains why no1 was showing a higher reading on my carb tune, 2 and 3 were about the same, and no 4 showing very little movement due to the air leak on the shaft seal.

Hopefully once my injectors are back I can balance the cylinders properly.

Thanks again robmack.

Bob

Tomorrow I will be able to test the bike .. at last. just waiting for the 3 bond sealant to cure overnight  on the AFM cover

I took some time to read up on how to set the mixture at idle and with the throttles open, via the AFM.

I ordered a gas analyser off ebay .

With the bike warm and a fan running in front of the rad I calibrated the analyser.

I set the idle mixture  to around 2% using the allen key adjuster, the engine revs increase slightly when the starter button is pressed , so its not far off.

Achieved 1.8% main mixture by moving the potentiometer wheel clockwise by four notches.

Rebalanced tb,s and idle setting 

Given these cheap analysers run to 0.5% error, I will confirm through checking the colour of the plugs.

Now my injectors have been done , I only need to pull one plug to check colouring.

The analyser I got was an older model with the needle, then found out that the later digital display unit is more  accurate and reacts much quicker to changes.  hey ho..

Having read about the need to check and probably reset the mixture, I was quite apprehensive about fitting the bigger tbs.

Thanks to all who have contributed on the TB  swap.

Bob

Started bike up this morning and took her for a 20 mile run, mixed with fast roads to begin with and then slower roads back to my house.

Noticeably smoother through the rev range and at higher cruising speeds now injectors have been done.

Didnt really notice the "startled wombat " that Dai spoke of, will open her up through the lower gears next time.

Athough I had adjusted the mixture using the gunsens meter, with its built in 0.5% accuracy, I was dreading pulling the plugs when I got back .

I was so happy to see all four plugs a really nice even biscuit colour all the way round on the  electrodes, with the outer edges completely dry.

My plug number one prior to having the injectors done was always white on the electrode, and the other three only showing any colour one one side of the electrode, not all the way round.

Shows the importance of having efficient injectors.money well spent.  Thanks to the guys at Swadlincote diesel injection services, in the east midlands. 

Minor adjustments  for throttle and " choke " free play and she is good to go.

Air flow meter spring tension adjustment on my unit was four teeth clockwise ( lean ) form the top when viewed with the adjustment locking arm at 11 oclock.


Hope this helps someone.

Happy days again 

Bob

Nice to hear Bob!

Have a good time
Cheers

Thanks Chocolate.

My bike set up is as follows:

Professionally cleaned k100 injectors with new "o" rings

New fuel filter

Fuel pump gauze filter checked.

New air filter

New coolant temperature sensor

1100 throttle bodies 

k1100 FPR

Throttle cable outer shortened by around 14mm to ensure full cam rotation

Throttle stop screw arm reduced in width to allow for clearance from no 2 bottom inlet stub rubber 

Fuel pressure 38psi between feed from tank and fuel rail.

Slight adjustment on the AFM bypass screw

Four teeth leaner on the AFM vane spring adjustment, ie clockwise 

All plugs now a light biscuit brown.

Again, thanks to everyone who had already done this for their help .

Bob

audibob wrote:Thanks Chocolate.

My bike set up is as follows:

…

All plugs now a light biscuit brown.

Again, thanks to everyone who had already done this for their help .

Bob

 
A lot done, running good I presume.

This Browned Butter Biscuits you mean ;-)



Cheers

audibob wrote:Didnt really notice the "startled wombat " that Dai spoke of, will open her up through the lower gears next time.

Didn't know you had wombats over there.

Update on my 1100 TB swap.

Although my plugs are now a good colour after a fast run  I was not convinced that the acceleration through the gears , or 5th gear roll on power was as it should be .

A couple of wombats short of a full house ....

I took my bike to my friendly mot guy and hooked her up to his machine.

1.78 at idle and 0.66 at 3k so running weak 

That was interesting given the colour of the plugs .

Reset the air flow meter spring setting to its original position and had her retested.

5.5 at idle with 1.6 at 3k so slightly rich .

I have a old  gunsens CO meter which  I set it up and tweaked the AFM  bypass screw and reduced the idle CO reading a little.

Took her out today and roll on power is back.

Dropping to third gear at 50 and opening her up now results in a full pack of wombats with an extra one past 6k  so my TPS is working ok.

Grin factor is back , and then some.

Plugs are still nice and light brown.

Was this conversion worth it.

Yes, Definately a little more power.

Smoother acceleration.

Injector refurbishment was crucial.

What was not good.

Adjusting the mixture . Should have had the mixture checked professionally before opening the AFM  

At least I had the sense to mark its original position...

I seemed to have spent more time working on her than riding her lately, but it was worth it.

Thanks to all again for their inputs.

Bob

See - told ya!

Thanks for the update Bob. 
Good to hear that you have finally got to the end of the project and are happy with the result too.

Still waiting to see you and Mrs Bob down this way....

Hi BAE 

I intend to travel to somerset within the next few weeks, so will let you know when and we can meet up somewhere.

Bob

audibob wrote:Hi BAE 

I intend to travel to somerset within the next few weeks, so will let you know when and we can meet up somewhere.

Bob

I know you said you had family in the area, but it you need board, lodging and secure parking (and 3 pubs within staggering distance), then let me know and I will PM you my address/contact details etc. Only day I know that I'm definitely out of town is 30 Sep as I'll be returning eldest daughter to her student digs on that day...

Thats great BAE , will pm you when I am coming down your way.

Bob

audibob wrote:Thanks Chocolate.

My bike set up is as follows:

Professionally cleaned k100 injectors with new "o" rings

New fuel filter

Fuel pump gauze filter checked.

New air filter

New coolant temperature sensor

1100 throttle bodies 

k1100 FPR

Throttle cable outer shortened by around 14mm to ensure full cam rotation

Throttle stop screw arm reduced in width to allow for clearance from no 2 bottom inlet stub rubber 

Fuel pressure 38psi between feed from tank and fuel rail.

Slight adjustment on the AFM bypass screw

Four teeth leaner on the AFM vane spring adjustment, ie clockwise 

All plugs now a light biscuit brown.

Again, thanks to everyone who had already done this for their help .

Bob

Since I already have all of the parts on hand I think I'll give this a go on my K100 this summer.  Thanks for this summary.  It doesn't show a timing advance. Did you advance your timing?

How did you shorten the throttle cable sheathing?

When I did the K11 TB swap some years ago instead of shortening the cable sheath I ground a few mm's off the split 'barrel' of the K11 throttle arm at the TB rack.

"and 3 pubs within staggering distance"


Some days I think I'm just living in the wrong place....

Woodie wrote:"and 3 pubs within staggering distance"

Some days I think I'm just living in the wrong place....

Down Undah we don't bother with any staggering. We do the pub crawl.