16V and 8V

[thebob]

"
frankenduck said.

They have very different FI/engine management systems (analog L-Jetronic vs. digital Motronic) so you'd need to swap wiring harnesses as well. "

Physically would a 16V head fit? I realize that the injection systems are different, but surely as long as the injectors have similar flow, and fit physically the system wouldn't "know" its on a different head.

Do all of the transmissions fit all of the K100 engines, or are they different for para and mono lever?

[Rick G]

The cylinder heads are not easily interchanged. You would at the very least remove the pistons and put new flycuts in for the 4 valves.
All the gearboxes are interchangeable although the k75 does have a slightly lower 5th gear I believe.

[Inge K.]

All the gearboxes are interchangeable.

Exept that that the paralever boxes have a mounting lug for connecting arm to the FD,
which isn`t present at the monolever.

Inge K.

[frankenduck]

All the gearboxes are interchangeable although the k75 does have a slightly lower 5th gear I believe.

Yes, with the exception of the tangs for mounting the paralever as Inge pointed out the transmission housings are identical and will bolt right up.  (My K75 has a K1100 transmission.)

The K75 transmissions  have a 1.67 ratio in 5th gear While the K100s and 4V models have a slightly "taller" 1.61 gear ratio.  It's only about a 3% difference.  All of the other gears are the same.

[thebob]

Good this is all interesting.

So it sounds like a 16V head swap would need 16V pistons, so it would probably be better to just change the whole engine.

Interchangeable transmissions are also good to hear.

I understand that the K100RS has a higher final drive than the other K100's. Which transmission has the lowest ratio?

[frankenduck]

Transmission internals are identical.

Most K100RSs and I think all K1100RSs have 31/11 FDs.

[frankenduck]

You'd be much better served (time, cost and yen-wise) by just buying a 4V K100RS:

10 more hp
Better front and rear suspension
MUCH better front brakes
Wider wheels with radials

[thebob]

You'd be much better served (time, cost and yen-wise) by just buying a 4V K100RS:

Because of the way registration works here, it is cheaper to register the older bike, and the testing isn't so stringent.

1100's fetch top dollar, but K100's are very cheap.

Call it a mind experiment, I think the upgrade path would go something like this.

I believe that all tuning should start with suspension and brakes so.

1. 1100 Rear wheel (because it slots straight in)

2. 1100 front wheel, discs, forks, triple trees (yolks), calipers, fender (mud guard)

Then it gets tricky,

3. 1100 throttle bodies and injectors only? or 1100 complete engine with throttle bodies and injectors.

Any other parts that you wold consider as upgrades?

[thebob]

Ah! the Mono/Para question! Simpler, lighter, shorter verses half a fix for a problem that can be ridden around.

The para lever 'improves' the jacking effect, but because the pivots don't form a perfect parallelogram they don't eliminate it completely. More moving parts, and a longer wheelbase are the negatives. I wonder which is the easiest to maintain and which is more reliable.

I think that decision is a personal preference one. I hope I don't get to ride a para lever, cos then I might want one.

[Rick G]

I think from memory yours is an 8V K100RS and if so the three spoke K1100RS wheel does not fit straight in, it will sit 14mm of center to the left and the stands will have to be modified.
If one like that was bought to me for a roadworthy certificate I would knock it back.

[frankenduck]

It'd take a lot of work to make a K1100RS wheel fit an 8V front end.  I'm not even sure the forks are far enough apart but I'm pretty sure that the rotors wouldn't line up with the calipers.

I guess the mono vs. paralever thing is a personal preference thing.  I REALLY wanted to keep my K75 as a monolever for the 32:10 gear ratio but after putting some miles on it the jacking was just too annoying (even with only 75hp) so I swapped in a 32:11 K1100LT paralever.  I'm much more happy with it now.  Feels more "planted" when riding and no noticeable jacking.

Since the difference in shock lengths is about an inch and they're mounted at roughly 45 degrees then the wheel base is only increased by about 0.707 inches - so the wheelbase is only a little more than 1% longer.  Maybe that matters to a pro racer but it certainly doesn't to me.

Another added benefit of the paralever system is that the drive shaft splines don't wear out like they do on a monolever.

[Rick G]

I was refering to the rear wheel, I forgot to say that DOH!
The front wheel will fit but with a heap of stuffing around. A spacer needs to be made and the discs from a late R100rt (mystic) will fit and the K1100 calipers will bolt on with those discs.  I reckon you would be better of using a complete K1100RS front end and then you will get the bigger discs.

[thebob]

I think from memory yours is an 8V K100RS and if so the three spoke K1100RS wheel does not fit straight in, it will sit 14mm of center to the left and the stands will have to be modified.
If one like that was bought to me for a roadworthy certificate I would knock it back.

Thanks for that it is a game changer! But mysterious. 14 mm is a long way out of line, I'd consider a bike set up this way dodgy.

 It sounds like all "paralever wheels can be interchanged but, not with mono lever ones. Unless the early paras use some kind of spacer.

[frankenduck]

I think from memory yours is an 8V K100RS and if so the three spoke K1100RS wheel does not fit straight in, it will sit 14mm of center to the left and the stands will have to be modified.
If one like that was bought to me for a roadworthy certificate I would knock it back.

What does "knock it back" mean down there?  Here in the states that refers to drinking.

[robleyd]

In Oz that generally means a rejection.

"I asked her out for a date but she knocked me back"

[Inge K.]

Thanks for that it is a game changer! But mysterious. 14 mm is a long way out of line, I'd consider a bike set up this way dodgy.

Have a look at post #319 in this thread.

Inge K.

[mystic red]

Thanks for that it is a game changer! But mysterious. 14 mm is a long way out of line, I'd consider a bike set up this way dodgy.

Have a look at post #319 in this thread.

Inge K.

Agreed Inge,
I don't think I'm the only one here who runs a RS/RT rear wheel on an 1100LT, which is offset. Made no difference in handling.

[thebob]

After reading that topic, and the more I think about it, the less worrying it seems.

Would it have the same offset in a paralever rear end?