6 replies to this topic

[Tor]

Hi all,

 

Not been on here in a while, mainly as I spent a year in Greece and owned a Dorsoduro 750 for most of that time. Good, unabused TDMs are few and far between there, so I went for an Italian job and had much fun. Not in Athens city, which is slippery AF and has insane driver behaviour plus congestion, but on the open roads. I mean, the Peloponnese is brilliant for riding. But I digress.

 

My 9er was put in storage, and I found a cheap ECU in Norway before emigrating. I delivered it in person so had a good chat with Spiros (Samios) about it. I didn't want the fuel cut as I enjoyed the engine braking and hate popping in the cans, but he convinced me to go for it for all the other, better, reasons. Anyway, I've had a good read-through of the related threads here and am all excited to get riding with it.

 

Samios said to block off the breather pipe to pretty much eliminate popping. What's the experience of others about this?

 

Has anyone got the final word on torque limitations also in 1st?

 

Lastly, my replacement ECU is a -00 suffix one, mentioned on the JBX site as a 'faulty', recall type with poor low-rpm fuelling. I assume this doesn't matter as long as it's been remapped, right?

 

As soon as I have more than a few evening hours of babysittage to hand, I'll get it fitted along with a K&N air filter. Couldn't find the recommended DNA one, new or used, anywhere...

[ramo]

Tor,

 

contact them regarding flashing a -00 suffix one, I bought one of these with the intention of Samios flashing it, but  it was a no go,

 

they said they would/could not flash it for me.

 

This was a couple of years ago, so things may have changed

[fixitsan]

I've got a Samios reflash ECU, currently not fitted.

 

I think the torque limiting is 'variable' in terms of being able to notice it, I think there's a slight improvement going up the gears and i think econpomy improved, but I never was willing to pay for a dyno session to see if the claims are realistic or not.

 

The fuel cut is of definite benefit from my point of view.

 

The bike I had fitted it to went over 115,000 miles and started to smoke a bit ,doubtfully due to the remap at all. I hammered it,  so I sold it cheap and found another bike. One with a Power Commander PC5. I quite like the PC5 (forgot which map I use) but fuel cut wasn't disabled. My problem with fuel cut is the transition from overrun to light throttle switched between full engine baking and none at all, which I thought made it a bit jerky

 

So I looked at a way to disable fuel cut and figured it out, made a prototype circuit which is very simple to build and install and added that to the bike. You basically cut one wire going into the ECU and the end which is left going into the ECU you connect to ground. I feel this would work for most Yamahas of around the same period which uses a similar ECU.

 

It felt great to me. But a couple of readers said they would still like to keep engine braking while slowing down so my compromise was to disable fuel cut in normal use, but when the brake light is activated fuel cutting is enabled again to re-enable engine braking, sort of the best of both worlds..

 

Now it feels like it's running on tuned carbs, and if you don't bring on the brake light while slowing by activating the brakes, you get burbles from the exhaust, and I like that.

 

If you are willing to pay a deposit I could send you the remapped ECU to let you try it out if you like, and I'll go and find the fuel cut defeat device stuff I posted here and give a link to it

 

I find the PC5 and fuel cut gives a similar effect to the remap, although it probably isn't as smooth in all respects as the remap is, maybe it's less economical I don't know really but only a dyno would reveal the truth.

Here's  the fuel cut thread.

The first few pages are of some technical methods I was going to use, not just to cut fuel but also reprogram the ignition and fuel injection without using a PC5.

 

As the story went on it became clear that cutting one wire gives a basic fuel cut defeat, don't need any electronics. If you want engine braking when the brake light comes on you only need to add a 12V SPCO relay. £5 covers it all.

 

 

Fuel cut thread http://www.carpe-tdm...9&hl=+fuel +cut

Here's the specific message with photos of exactly the wire at the ECU I cut. If your bike has the same wire then fuel cut will almost certainly be able to be defeated by cutting it and grounding the ECU side wire tail

 

http://www.carpe-tdm...=38859&p=401695

 

 

 

I've also advanced the ignition timing about 4 degrees, to increase performance further, and because we never use anything less than 95 ron fuel in the UK

Edited by fixitsan, 27 March 2026 - 02:17 pm.

[Snowbird]

I looked back on that thread briefly and was going to ask about the 4° advance then remembered it was for a 9er, is it the same for a 4TX and what was involved?

I'd like to give it a go but being a tightwad I'd rather ask someone that's done it than buy a gasket just to look.   

[fixitsan]

I looked back on that thread briefly and was going to ask about the 4° advance then remembered it was for a 9er, is it the same for a 4TX and what was involved?

I'd like to give it a go but being a tightwad I'd rather ask someone that's done it than buy a gasket just to look. 

 

Very wise plan.

 

It's almost identical on an 850, this is a picture for the 900.

You need to remove the pickup coil and slot the mounting holes sideways, in the direction of the red lines in the image. I think I worked out that moving the pickup 1mm sideways gives a noticeable improvement a bit under 4 degrees, maybe 1.5mm is about your limit.

It needs to move in the opposite direction to the rotation of of the rotor in order to advance the timing

When drilling/dremelling the mounting holes sideways, wrap the pickup in self adhesive tape first, to keep the magnetic steel shavings off the face of the pickup coil, removing it again before testing.

 

 

 

Stats3red by Chris Barron, on Flickr

Edited by fixitsan, 27 March 2026 - 10:23 pm.

[Snowbird]

 Looks simple enough, may have to order a spare gasket then.

[fixitsan]

 Looks simple enough, may have to order a spare gasket then.