72 replies to this topic

[fixitsan]

I've done this mod to the 850....and it works well, more responsive, pulls harder. I did it this morning before a 250 mile round trip up north into the hills, over lots of different types of roads

 

I used the same method as when i did the 9er, by slotting the mounting screw holes of the ignition pickup (after grinding off the locating lugs.

 

No sign of preignition and the temperature doesn't seem to have been affected

[TYREDNGRUMPEE]

Still got the 1st and 2nd gear wires sending to the ICU from the selector barrel?

[fixitsan]

Still got the 1st and 2nd gear wires sending to the ICU from the selector barrel?

I haven't removed them......if nobody else did then they're still in place......i guess they're low gear ignition retardation. ..

[TYREDNGRUMPEE]

they're low gear ignition retardation. ..

 

major buzzkill

[fixitsan]

 

major buzzkill

 

 

Probably why the bike felt good today after advancing the ignition.

 

 

Best thing was roll on in top gear, much snappier than before modding

 

When you disconnect the wires should they be left floating instead of being either grounded or pulled up to +12V ?

[fixitsan]

Checked the WD.... both wires for 1st and 2nd go back to the white wire in the 6 way ignitor plug, so I've popped the wire out from the plug at the ignitor.....so much quicker and cleaner than taking them off the switch itself.....I'll try to test it tomorrow

[TYREDNGRUMPEE]

.....I'll try to test it tomorrow

 

Thanks very much.    Standard disclaimer and all that stuff 

Edited by TYREDNGRUMPEE, 12 November 2016 - 10:24 pm.

[fixitsan]

Wheelie prevention mode disabled     (or is it gearbox saving mode ?   ....whatever ! )

[dmmsta]

I've done this mod to the 850....and it works well, more responsive, pulls harder. I did it this morning before a 250 mile round trip up north into the hills, over lots of different types of roads

 

I used the same method as when i did the 9er, by slotting the mounting screw holes of the ignition pickup (after grinding off the locating lugs.

 

No sign of preignition and the temperature doesn't seem to have been affected

Is there a thread on this...

I'm by no means a fully qualified fettler, but I'm intrigued by this whole subject...

[fixitsan]

Is there a thread on this...

I'm by no means a fully qualified fettler, but I'm intrigued by this whole subject...

 

This is what i did for the 900 - slotted the pickup mounting holes, in order to slide it towards the rear of the vehicle to advance the static timing. ..

http://www.carpe-tdm...=32724&p=330529

 

More info around that post

[dmmsta]

 

This is what i did for the 900 - slotted the pickup mounting holes, in order to slide it towards the rear of the vehicle to advance the static timing. ..

http://www.carpe-tdm...=32724&p=330529

 

More info around that post

Reading with interest

 

Thanks

[fixitsan]

 

Thanks very much.    Standard disclaimer and all that stuff 

 

 

Yup that feels better.

 

No sign of pinking in any gears, even when lugging the engine, when it would normally be most evident. My last fuel fill was with 95RON fuel too, i would think there is little fear of advancing too much...... 1mm of movement equates roughly to 1 degree of advance, even if you went to 5 degrees I doubt preignition would occur

 

Also, try as I might, I couldn't get any decent heat into the engine. It's about 4 degrees out there and I struggled to ge

t the temp gauge upto  1/4...... it's possible the 'stat is stuck open or even not present (I haven't checked it), but even then if the engine was pinking the temperature would have been going up rapidly

 

I would say advancing the timing gives about the same benefit as disabling learner mode on gears 1 and 2, and you get it in all gears

[Bjørge]

 

Also, try as I might, I couldn't get any decent heat into the engine. It's about 4 degrees out there and I struggled to ge

t the temp gauge upto  1/4...... it's possible the 'stat is stuck open or even not present (I haven't checked it), but even then if the engine was pinking the temperature would have been going up rapidly

 

Part from running idle, I've never seen the temp gauge move noticeably....

[fixitsan]

 

Part from running idle, I've never seen the temp gauge move noticeably...

 

 

Not surprising really, given that  the standard static ignition timing is so far retarded

 

Late ignition timing puts more heat in the exhaust headers and less in the cylinder...this video shows it in the extreme...

 

 

 

Look what happens when 900 owners play with the CO setting and the exhaust headers turn blue from the heat. That wouldn't be as likely to happen with less retarded spark timing

Edited by fixitsan, 13 November 2016 - 10:11 am.

[fixitsan]

 

Part from running idle, I've never seen the temp gauge move noticeably....

 

 

 

Not ever ridden in Norway, but I hear it can be very cold !

[Bjørge]

 

 

 

Not ever ridden in Norway, but I hear it can be very cold !

 

Well, I never (or hardly ever) ride below 0 (Celsius), "normal" part of the season maybe between 6 and 26. Extremes below and above, but not very often. 

 

Only time the temp gauge shows any sign of moving is at idle or crawling in city center, etc.. If it's a really hot day the fan may even start  (then you know it's a hot day).

 

Why is it that ignition is retarded from factory ? Any advantages ? Environmental ?

[fixitsan]

Factory standard bikes need to run on the worst available fuel, in the US and other areas you can buy 92 RON fuel.

To prevent preignition with 91 or 92 RON fuels the ignition is retarded (actually its still advanced, but not as much as it could be if higher quality fuel use can be guaranteed )


Unless an engine is fitted with a knock sensor then the timing must be factory set for the worst case scenario. If a knock sensor is fitted the timing can be advanced as much as is possible to just prevent preignition, and then when high quality fuels are used the engine peak performance can be increased accordingly.

Like most bikes in circulation, TDM doesn't have a knock sensor so timing is factory set for the lowest quality fuel. If you can always access at least 95 RON fuel a few degrees of advance is usually harmless, and usually improves the overall responsiveness of the engine

Edited by fixitsan, 14 November 2016 - 11:41 am.

[Bjørge]

Ok, I see.... My old Russian '79 Lada 1500 had a thumbscrew for easy ignition advance adjustment - guess it may be needed with the somewhat varying petrol quality of the old days' Russia....

[fixitsan]

I have found over the years that the knocking/pinking sound of preignition is a good enough guide as to whether or not there is a timing problem on an engine.

 

Usually, before any serious damage occurs, (such as burned piston or valves), a good reliable telltale of a problem is the condition of the spark plugs. With preignition the spark plugs are almost always burned in some way....(see below)

 

 

 

 

 

If your spark plugs have the correct light/mid tan colour and the electrodes show no signs of overheating, and you can't hear any knocking, it wouldn't be unreasonable to assume that your timing is set  within the safe range of operation

 

 

Unlike this.......

Edited by fixitsan, 07 January 2017 - 06:22 pm.

[tdmpaul]

have you any pics of the gearbox wire your disconecting fixitsan? i havnt seen this mod before but gona give it a try while im having a sorting of my bike this winter.