278 replies to this topic

[Catteeclan]

I'm thinking of leaving the top cover off altogether once the unifilters are installed.

[frits44]

I'm thinking of leaving the top cover off altogether once the unifilters are installed.

 Good morning Catteeclan,

 

You can do that, but it makes more noise with full throttle.

 

If you install unifilters  use big ones from a big engine, what I mean is each filter from a 1000cc engine or more.

 

So your engine can breath free air without air resistance.

 

Have a nice day.

 

Greetings, Frits from Holland

[frits44]

I'm thinking of leaving the top cover off altogether once the unifilters are installed.

 

hello Catteeclan,

 

This for example, it will fit on your TDM 900 ????

 

http://www.yamahasup...p?topic=9068.30

 

 

greetings, Frits from Holland

[adamg]

Another idea to add into the mix. My throttle sync screws are about 2.5 turns out to get the correct vacuum readings and to balance them. This raised the idle speed significantly, so I turned out the idle screw back to bring the idle back to 1200rpm. Seems like this has helped low speed riding.

[frits44]

Another idea to add into the mix. My throttle sync screws are about 2.5 turns out to get the correct vacuum readings and to balance them. This raised the idle speed significantly, so I turned out the idle screw back to bring the idle back to 1200rpm. Seems like this has helped low speed riding.

 

Good morning adamg,

 

The throttle sync has to be correct, how too do it you can read it on the site of JBX.

 

There is a screw on the side of your bike for the correct idle.

 

http://www.jbx9.16mb...x.php?page=SYNC

 

Greetings, Frits from Holland

[adamg]

If you change the idle screw remember to adjust the TPS position so it runs through the correct range

[fixitsan]

So I changed the two long intake runners for two short ones, which seems to have improved responsiveness.

 

[attachment=8174:longintakes.jpg]

[attachment=8178:shortintakes.jpg]

 

 

 

 

 

I also cut a little bit more from the right side of the airbox cover and removed some foam from the right side under the tank. There is a large gap where fresh air can enter from the right side above the clutch housing, but there is also a lot of space above the swingarm where the cold air can be drawn from the rearso maybe it's no different...I don't think engine heating makes too much of a differenec, but I live in mostly colder temps most of the year. 20 Celsius is very unusual

 

[attachment=8171:coverfit.jpg]

[attachment=8172:coverhand.jpg]

[attachment=8173:covermounted.jpg]

 

 

I had toyed with the idea of adding a low value resistor in series with the IAT and it has made a noticeable difference . Acceleration under load is more brisk. I chose a 330 Ohm resistor because it is only going to be significant at warmer temperatures....at 19 celsius here (positively balmy for Scotland), it makes enough of a difference for me to think it worth mentioning.

 

The ECU wire to cut is brown/white.

 

[attachment=8175:plug1.jpg]

[attachment=8176:plug2.jpg]

[attachment=8177:plug3.jpg]

 

 

Testing the IAT before the changes I got the following results

 

Temp©......Resistance(Ohms)

10................3500

15................3000

25................2000

35................1500

 

So at a running temps between 15-25 degrees, the resistor is worth about 4 degrees celsius. Below 10 degrees it's wortth less, and above 25 it is worth more. This non-linear effect might be favourable to a linear effect, given the known effect  which passive heating has on the IAT.

 

 

In terms of the effect to the overall AFR.......the CO adjustment still takes care of the very low load/low speed range, the O2 sensor still takes care of the midrange and cruuising speeds, and the ECU now enrichens a little bit more in open-loop mode when under acceleration, because it believes the air is slightly cooler than actual. My mpg was normally great, 190miles and still two bars on the gauge to go, so I should notice if it turns poor

Edited by fixitsan, 14 January 2017 - 12:04 pm.

[frits44]

fixitsan,

 

Nice job you did and good information.

 

I am still looking for other air filters.

 

Greetings, Frits from Holland

[fixitsan]

Ive got the k&n filter Frits.... works great . You can use the standard airbox so the other pipes/breather are retained

[frits44]

Ive got the k&n filter Frits.... works great . You can use the standard airbox so the other pipes/breather are retained

 

 

fixitsan,

 

I am going too remove the air box completely and fit other air filters.

 

Why, because I can see on your pictures that the opening for the air inlet between the cover air box and the fuel tank 

 

is very small. The engine can breathe very difficult by this small opening.

 

I am going too test it.

 

Greetings, Frits from holland

[fixitsan]

That is true Frits, but, if you are running at 1200rpm you don't need to do that 

 

 

Really, if you are concerned, just remove the foam around the tank, it will increase potential maximum airflow by 4 times

Edited by fixitsan, 30 May 2016 - 09:51 pm.

[JBX]

Now have some fun with a capacitor between the TPS line and the sensor ground.

Test using 1 to 50µF caps and you'll be amazed !

 

(and please clean that bike, how could a TDM lover keep dirt & dust while toying with the inside of his bike !)

[fixitsan]

Now have some fun with a capacitor between the TPS line and the sensor ground.

Test using 1 to 50µF caps and you'll be amazed !

 

(and please clean that bike, how could a TDM lover keep dirt & dust while toying with the inside of his bike !)

 

 

I'ld thought of a capacitor, it's going to smooth the response isn't it ?

[JBX]

Yes, the capacitor will smooth out the TPS signal / throttle response.

[frits44]

That is true Frits, but, if you are running at 1200rpm you don't need to do that 

 

 

Really, if you are concerned, just remove the foam around the tank, it will increase potential maximum airflow by 4 times

 

Good morning fixitsan,

 

I am going too test it driving without air box and use other filters, I just want too know how the engine responds

 

I always can reverse it. And It is nice and fun too test thing, it can only be better not worse.

 

And yes I can drive now my machine in very low rpm and it is nice you have seen my movie, it can be done.

 

I will make  pics if I have new air filters installed.

 

Have a nice day,

 

Greetings, Frits from Holland 

[fixitsan]

Yes, the capacitor will smooth out the TPS signal / throttle response.

 

Was just thinking about this. I suspect it will put the TPS out of sync with the physical throttle butterfly valve..... could cause all sorts of issues I think

[JBX]

It obviously depends on the value of the capacitor !

 

When I did the tests some years ago I noticed too high values (above 10µF afair) drove the ECU into some sort of confusion about the throttle response. Of course nobody would expect anything different !

 

There was a value which gave good smoothing results without the ECU going mad.

I should do the test again...

 

Different raise & release values should also give a better result, with raise time constant being lower than the release time constant.

Something like the adsr circuit found inside sound synthesizers...without the decay/sustain parts !

[fixitsan]

Hysteresis ☺

I think the problem comes when running at light load, then cracking open the throttle wide....the butterfly opens, the pressure sensor sees the pressure raise, but the TPS is slowed by the capacitor.

[JBX]

No hysteresis involved here (not a trigger), this is just a matter of RC time constant.

Raise time constant should be kept shorter than the release time constant.

[fixitsan]

No hysteresis involved here (not a trigger), this is just a matter of RC time constant.
Raise time constant should be kept shorter than the release time constant.

You can only have a single time constant with one capacitor, as Tc is fixed due to using a fixed capacitor and fixed (very low due to wiring) resistor.


Could you draw a quick schematic of how to achieve what your saying with a single capacitor. Thanks

 

 

All conventional electronic knowledge points to T = RC. T, the time constant, is the time taken to charge the cap to 63.2%., and it takes roughly 5T periods to consider it almost fully charged

 

 

With a single capacitor , in a fixed circuit, the time constant cannot be changed, and the time constant remains the same for both  rising  (charging) and falling(discharging) voltages

Edited by fixitsan, 03 June 2016 - 06:56 am.