audiomick

Not magical, but I gather Meinolf took the time to sit down and do the maths to find out the optimum number based on the numbers in the map. As Phil said, the result is, not surprisingly, well within the tolerance stated in the workshop book. At least in the one for the V11.

For which a lot of the credit goes to Barry Sheene. Of topic, I know, but credit where it is due.

Two days ago we had about 12"C. Yesterday and today about 8"C. Some rain, and lots of wind. It's still cold, but it's like Spring sent a postcard with the message "hey, I'll be round in about 6 weeks. See you then".

My answer is also on its way. Thanks.

Yes. It's the same principle, but reversed, as the logarithmic faders on an audio console. They do big steps at the bottom of the range of movement, and small steps towards the top of the range around the nominal level point, marked 0 dB. Typically, the first centimetre or so (depending on how physically long the fader is...) above and below 0 dB makes changes in the range up to +/- 10 db. Down at the bottom end, the same physical displacement of around a centimetre is more like 40 dB. The reason is, if you have your signal structure set up "right", your faders are all going to be somewhere near the nominal level, i.e. physically near the 0 dB mark. Subtle changes in the mix require a definite move of the fader to make a fairly small difference. The same definite move down towards the bottom of the range (where the fader theoretically only passes through during a complete fade-out) results in a level change that is anything other than subtle. Getting back to the motorbike: riding on the street, we spend most of our time below half-throttle or so. The non-linear TPS means that in that range, a specific movement of the throttle will trigger more break points than the same physical movement above the point where the characteristic changes, i.e. above the 30-odd degrees that Phil referred to. That makes sense: letting out the clutch, riding in traffic, accelerating out of the corner (road or race-track) all require fine control of the throttle, and all happen at (roughly speaking) less than half throttle opening. Above half open, it is generally about maximum acceleration, and tends to be a bit "digital", i.e. full throttle or closed throttle. Therefore, it is theoretically an advantage to have the ECU receive more break points in the lower range of throttle opening at the cost of larger jumps in the upper range of throttle opening. On top of that, there is also the thing that the relative change of the size of the air passage past the throttle valve is greater in the lower range of opening than it is in the upper range. That means, once again very roughly speaking, a change from "nearly shut" to "open a bit" might be equivalent to, for instance, "a bit over three quarters" to "flat out". Therefore, the three degrees difference between 5.9 and 8.8 may effectively not be so drastically less than the 12 or so between 50.4 and 60.1 as it seems at first glance. Having written all of that, the manufacturer apparently decided it all wasn't worth the effort. I gather newer TPSs than the ones in our V11s tend to be linear.

Not likely for me, but I wish I could. Thanks for the info.

No doubt that was referring to the lower range of the non-linear TPS. I saw a graph somewhere. The non-linearity is not a continuous curve, but rather a steep straight line, a bend, and another less steep straight line. Yes, I was also very suprised at how large that range is. Thinking about the numbers involved, I can see it as a pragmatic compromise within the context, but really accurate is mostly better. And lets me sleep better.

A further quote from Meinolf from the same post, which confirms what Phil wrote about the non-linear response of some TPSs, I believe the earlier ones, which includes the V11: "The difference may seem small, but a meticulous adjustment of this value is absolutely necessary. The interpolation points are so close together in the low load range that a shift of one row can quickly occur due to normal wear and tear in conjunction with the function of the ADC. And this is immediately noticeable in the low load range." Meinolf was writing regarding a California Vintage, but I believe the ECU and throttle bodies were more or less the same as the ones in the V11.

Quote from Meinolf (via DeepL.com) from the German forum: "Furthermore, the 8-bit ADC used in the 15M/RC has a very low resolution, it can only calculate in steps of 5V / 256" Regarding 8-bit resolution: https://en.wikipedia.org/wiki/8-bit_computing#Details 256 steps. Regarding what Phil wrote about the non-linear TPS response, yes I have read that elsewhere, and consider that to be accurate. @docc if you think this is worth splitting off, go for it.

Another another thought: I just did some sums. As I mentioned further up, I'm quite pedantic by nature, so don't take this as a "near enough is good enough" thing. I observed today that the "full range of travel" of my TPS was from the set 157 mV at fully closed to just over 4.8 V at fully open. As far as I know, the TPS / ECU combination has a resolution of 256 steps. So... 4,800 / 256 = 18.75 which means that the +/- 15 mV in the workshop book is less than one "step" in the resolution of the system, and 4 or 5mV variance is a relatively small value in the context.

Another thought regarding fixing the throttle valve down with cable ties, or pushing it shut to do the "base level" measurement: I observed today that pushing the throttle shut changed the measured voltage by about 4 mV. On the basis of that, I reckon there is no point in taking the extra effort to tie or push it shut. Make sure it is clean and unhindered, let it snap shut a couple of times, and do the measurement. Any further measures just wont make a significant difference.

There is hope. Get in touch with Scud, and ask him if he still has some available.

I'm very thankful that my Guzzis don't have 16" wheels. That is really hard. The Kawasaki GTR 1000 that I have (still, I've been meaning to sell it for about a year...) has a 16" rear wheel. The tyre is a 130/80 16. There are about three tyres on the market in total that fit.

Wheel bearing: what? don't know that one. Shift spring: no, not really, as far as I have been able to tell. A solution was found here in the forum. If you're lucky, you might still be able to get one. Look here (it's a very, very long thread, but interesting) : The relays: there has been quite some research done in that direction. Look here, also a very long thread:

Of course. The more accurate, the better. As it happens, I am quite concerned with accuracy. Some might even say "annoyingly pedantic". Looking at the "official" tolerance serves more to help me sleep well at night than to excuse my unwillingness to get it right. My difficulty is more in the direction of recognising when it is well and truly good enough.

I see your point, but I find that a V11 without that fairing looks half naked. The fairing balances out the bumptious rear end that they all have.

Finally got around to furthering the Quest to set the TPS base value. After a first attempt several weeks ago, in which I had neglected to screw out the idle screw and make sure the "choke" wasn't holding the throttle valve open, and I measured 500 mV, I did it right today. The TPS had apparently not been readjusted since the bike left the factory about 65,000 km. ago. There was still yellow and red sealing paint on both screws. What I found was 250 mV. I reset it, aiming for the 157 mV that Meinolf recommends. With the movement that happens when it is all screwed up tight, I landed at between 159 and 160 mV. Given that the workshop manual states a tolerance of +/- 15 mV, I reckon that is ok. After fiddling around with the "choke" a bit to see how it might be best set up, I tried starting it. The starter button funny business reared its ugly head again, but she started after about 4 or 5 depressing clicks. First time since about last June. Idle was ok to be going on with. I hope to be able to spend some more time on it tomorrow and finish off the "decent tune up".

Once again, don't stress youself. We're talking about a luxury product here. A couple of days, even weeks, wont break the bank.

mine's on the way too.

Docc referred to this thread, and I notice there hasn't been any photos for a while. Too busy riding, or what? There's about 3 inches of snow on the ground here, maybe even 5 or 6. I haven't ridden for months, and I'm a little homesick for Australia at the moment. Get your arses on the bike and take some photos.

Maybe not a scam, but definitely a bet. You bet that you are going to have a problem that the insurance will cover, and the insurance company bets that you aren't. All well and good, but somehow the insurance companies seem to always be able to set the odds.

It doesn't rain, but it pours.

Can't help myself... Has anyone here ever heard of Terry Pratchett?

I understand and like the obligatory third-party property insurance. What I really like is the obligatory insurance in the State of Victoria, Australia, of which Melbourne is the Capital. I.e. where I lived in Australia. Obligatory is third-party personal liability insurance. https://en.wikipedia.org/wiki/Transport_Accident_Commission Sure, if someone drives into your Porsche who is not insured, you have a material loss (no obligatory third-party property insurance there). The third-party personal liability insurance ensures that any and all medical and personal damage costs as a result of a traffic accident are covered. I know from second-hand experience that it works. A former girlfriend had a really nasty accident. Someone turned in front of her (she was on a bike) and cleaned her up. Left knee completely disrupted, two breaks in the right femur and both the right tibia and fibia broken. All the hospital and rehabilitation costs were covered, and she got enough personal damages to buy a house.

Mine, in Germany, is €177,- a year. That is only third-party property liability insurance, the legally required minimum. If I were to take out comprehensive insurance, I would be paying within 4 or 5 years what I paid for the bike over again, so I don't. I choose to try and avoid throwing it away instead, and if I do, it's my own stupid fault. If anyone else should drive over it, the bike would be covered by their obligatory third-party property insurance. But I try and stay out of the way of that too.