On a recent thread there was discussion about the pros and cons of the TPS.
I've tried the last couple of runs with it disconnected and find it much pleasanter and smoother, especially at lower speeds. Easier on my 6 rivet transmission,too.
It may be imagination but believe that when giving it a bit of stick for overtaking, its feels a bit flat.
I want to do Charlie's suggestion and tweak the TPS's setting to get the best of both worlds.
My problem is loosening the screws.
How do you get at them, particularly the inside one. Does the battery need to come out?
They've been there for 30 years and need careful persuasion.
Suggestions please.

Here's the cool tool for that job & lot's of others.......and CHEAP too.
I've had one of these in my professional tool box for 30 years. Couldn't possibly live without it.
http://www.sears.com/craftsman-offset-ratchet-screwdriver-set/p-00904116000P

Comberjohn wrote:
My problem is loosening the screws.
How do you get at them, particularly the inside one. Does the battery need to come out?
They've been there for 30 years and need careful persuasion.
Suggestions please.

A right-angled driver is okay as long as the screw is free. If it's not been disturbed for a long time you need to be able to put enough pressure on it to stop the driver destroying the head and that's not easy with an angled screwdriver.

The last TPS that I set hadn't been moved for years. I removed the coil cover and that gave me enough room to get a stubby Philips screwdriver on to it. I used one of a set that has an 8mm hex section near the handle (failing that, needle nose mole-grips will help). With an 8mm ring-spanner on that I could put pressure on the screw with one hand while turning it with the spanner.

Once it was free, I removed both screws, cleaned them then refitted them and the coil cover as from that point a right-angled driver worked fine.

With regard to setting the TPS, when rotating the throttle to full throttle how far before full throttle should the TPS activate the enrich signal?

On my K it appears to be 1cm of rotation when looking at the grip is this adjustable at all and at what point does it occur on other machines?

Wow ibj! That's expensive. I can buy something similar for £1($1.20) on the high street. Poundland. Isn't Chinese manufacturing wonderful.
Thanks for that tip but have tried something similar using a small ratchet handle that can hold a screwdriver tip. As Mike says, it just twists out as its been there so long.
I tried taking the coil cover off but think I need the stubby screwdriver and/or the needle nose vice grips.
We never need too much of an excuse to buy more tools, do we?

Regards how far the throttle turns, I'm not sure. I would imagine it would only be towards the end of the turn. Probably only enrichens it slightly.
Seem to remember from carb days that you need a slightly richer mixture for acceleration.
It may be imagination but I felt that it was flattening out slightly near peak revs when looking for that bit of acceleration for overtaking.
Really like the smoothness without the TPS so it has to be done.
By tweaking the TPS it means that the switch will enrichen slightly earlier on the throttle turn but don't see that as being too much of an issue. Might make it go even better!

twincarb wrote:With regard to setting the TPS, when rotating the throttle to full throttle how far before full throttle should the TPS activate the enrich signal?

On my K it appears to be 1cm of rotation when looking at the grip is this adjustable at all and at what point does it occur on other machines?

On the Jetronic ECU bikes, the TPS should measure zero ohms when closed and infinite resistance when open.

If you have a multi-meter, remove the connector to the TPS, attach the meter to the first and second connector of the TPS itself (counting from the outside in),



then rotate the TPS until it reads .00 ohms with the throttle closed. Open the throttle and the meter should register plenty of resistance.



This is for the 2-valve bikes, with the 4-valve models a different process applies (different contacts and a voltage measurement).

Got that Mike, I am more curious as to at what point the TPS says to enrich the signal at standard setup so it can be checked when the adjustment to "tune out" the idle switch side.

You are only talking about a very TINY change between active & inactive in the throttle closed position. We want the switch to almost connect (or disconnect, whichever is correct) at the idle stop position. The miniscule change at wide open throttle would be nil, like the difference between contact at 99.8% and 99.82%.
Will not change the WOT setting in any perceptible way.

I checked out where the switch actually operates and the switch closed after the butterflys went past the point where they were no longer effective because the shaft is wider than the butterflys. So from that I would day that you will get no difference at all in the WOT situation.

Surely the point is that the mixture is enrichened by the ECU at full throttle when the TB are fully opened.
My experience today with and without the TPS, seems to show that there is a slight boost to full throttle settings with it connected.
But there again, imagination is a wonderful thing.