53 replies to this topic

[slipperyox]

Bollox anyway. I guess I have some sort of frankentdm

[wicklamulla]

Can't remember who it was Wicky, long time ago.  iirc they altered the wiring and had both coils firing, as in wasted spark.

 

so is dare an advantage to that?

[fixitsan]

You could use 2 coils by putting them in parallel. The 4tx coil has one wire outlet, the 3VD coil has two wire outlets, It could work, it isn't what the ECU is designed to do but there might be enough of a safety margin to allow it to work

 

The 4tx wiring can  be modified to suit, but it would be very obvious that it was done by all the wire grafting joints. Someone very careful could have gone to the trouble of rewiring the plug (4tx and 3vd ecu plugs are different) in which case it wouldn't be obvious at first without checking the wiring colour codes with a wiring diagram.

 

Something in my mind about the throttle TPS sensor on the carbs, do all 4tx have a TPS, and 3vd does not ?

 

so is dare an advantage to that?

 

A bit extra redundancy. If one coil goes weak you can still limp home

[wicklamulla]

Thx, I'm guessing the original blew up and was replaced...

 Can the stock carbs and ecu of the 4tx run the 3vd p&p?

Bike runs ok, but would have expected more grunt 

this yer 1st TDM or bike of this type?  shud be grunty enuf, dares not alot of difference atween the 3VD / 4TX  in performance terms .

You could use 2 coils by putting them in parallel. The 4tx coil has one wire outlet, the 3VD coil has two wire outlets, It could work, it isn't what the ECU is designed to do but there might be enough of a safety margin to allow it to work

 

The 4tx wiring can  be modified to suit, but it would be very obvious that it was done by all the wire grafting joints. Someone very careful could have gone to the trouble of rewiring the plug (4tx and 3vd ecu plugs are different) in which case it wouldn't be obvious at first without checking the wiring colour codes with a wiring diagram.

 

Something in my mind about the throttle TPS sensor on the carbs, do all 4tx have a TPS, and 3vd does not ?

 

A bit extra redundancy. If one coil goes weak you can still limp home

all 4TX have a TPS,  3VD never had one.  it can be left unplugged but the dials may show up an 'error code' by sweeping around wildly but i'm sure this too can be avoided/disabled/overcome etc.

[dapleb]

Couldn't stink of a raisin 3vd crank cases couldn't be used.

Would be interesting to know if it's "100% 3VD" or just cases! Diff conrod length too on 3vd Vs 4tx?

[Apache]

[quote name="slipperyox" post="362985" timestamp="1530957959"]Bollox anyway.

Amen to that fella. Just ride it if all has been done well. You can't run a 270 deg 4TX crank on one coil so it looks like it's a 3VD. Keep an eye on the oil level. All 850's burn some. Almost certain the original went belly up for lack of oil...

[slipperyox]

Thanks all

[wicklamulla]

Couldn't stink of a raisin 3vd crank cases couldn't be used.

Would be interesting to know if it's "100% 3VD" or just cases! Diff conrod length too on 3vd Vs 4tx?

Payter i don't tink so, iirc the only differences were with the XTZ750 which has a different crank stroke?

[Hombre]

If you listen to the exhaust, the 3VD has an even beat, the 4TX not so.

[wicklamulla]

look at the TCI (CDI)  it will have 3VD or 4TX on a sticker.

[Rallyist]

It could also be a re-framed 3vd

[Bjørge]

It could also be a re-framed 3vd

 

A really, really hard philosophical dabate could rise out of this question.....

[MickC]

I put a 3vd into a 4tx just so i could hear the 3vd running.

Remove the 3vd case top under the black cover and bolt the 4tx oil tank on-- simple as that--

I then used  3vd wireing --main loom--will not fit the 4tx headlight loom.

coil thermostat and cdi

3vd cdi is under the seat lift seat and look

I have 4tx mk2 carbs on my 3vd so mk1 and 2 carbs will work just nothing to connect TPS and carb heating to --on a 3vd--

If someone has made the 4tx loom cdi etc work I personlly would get all 3vd stuff-- main loom cdi thermostat

Or get a 4tx engine.

 

With regards grunt,my 4tx does seem a bit more snappy when you twist the throttle as in top gear roll on but the 3vd pulls smoother which seems like its a bit flat but it pulls just as well -ish- in my opinion.What bike are you used to?

Edited by MickC, 09 July 2018 - 10:07 am.

[Bjørge]

With regards grunt,my 4tx does seem a bit more snappy when you twist the throttle as in top gear roll on but the 3vd pulls smoother which seems like its a bit flat but it pulls just as well -ish- in my opinion.What bike are you used to?

 

1 penny on 4TX has a lighter flywheel, hence quicker but less smooth pull on low rpms

[MickC]

 

1 penny on 4TX has a lighter flywheel, hence quicker but less smooth pull on low rpms

Surely if you put a penny on a 4tx flywheel you would make it heavier? and you would need to put two on at 180 degrees to balance it up

[slipperyox]

I put a 3vd into a 4tx just so i could hear the 3vd running.

Remove the 3vd case top under the black cover and bolt the 4tx oil tank on-- simple as that--

I then used  3vd wireing --main loom--will not fit the 4tx headlight loom.

coil thermostat and cdi

3vd cdi is under the seat lift seat and look

I have 4tx mk2 carbs on my 3vd so mk1 and 2 carbs will work just nothing to connect TPS and carb heating to --on a 3vd--

If someone has made the 4tx loom cdi etc work I personlly would get all 3vd stuff-- main loom cdi thermostat

Or get a 4tx engine.

 

With regards grunt,my 4tx does seem a bit more snappy when you twist the throttle as in top gear roll on but the 3vd pulls smoother which seems like its a bit flat but it pulls just as well -ish- in my opinion.What bike are you used to?

Use to r1150 boxsers.  which are only 77bhp or so. But very grunty. I ended up counting the teeth on both sprockets thinking it was over geared... Reading 60mph @ 3000rpm.  Each gear just feels to be too tall. won't wheelie without slipping the clutch . cdi is on front left under side panel, no sticker on it. 

[fixitsan]

Can you compare them with ebay ?

 

This is a 4tx cdi. It has a long multipin plug and a short 6-pin plug  (13 pins and 6 pins)

https://www.ebay.co....VkAAOSw8Pda-~-f

 

This is a 3VD cdi, it has 2 plugs, both with 4 pins but with one slightly longer with 2 empty places.

https://www.ebay.co....vAAAOSw8UtbMkLh

Edited by fixitsan, 09 July 2018 - 09:39 pm.

[MickC]

Slipperyox-- It would be nice if you have the time to photo your bike-- side panels air box and tank off (dont forget as already said turn off the fuel tap at the back of the tank) show the cdi /coil/thermostat so we can all see, not only are we trying to help BUT we want to know ourselves because we are nosey bastards.

[slipperyox]

Slipperyox-- It would be nice if you have the time to photo your bike-- side panels air box and tank off (dont forget as already said turn off the fuel tap at the back of the tank) show the cdi /coil/thermostat so we can all see, not only are we trying to help BUT we want to know ourselves because we are nosey bastards.

Ok. Removed tank and airbox.

CDI did have sticker, and its a 4tx. carbs have a tps . However only one coil, if you look in pic you can see the redundant connectors that I assume would go to the other one. Also there is another redundant two wire connector (black yellow and blue yellow)

and coil

 

Edited by slipperyox, 27 July 2018 - 05:02 pm.

[Apache]

3VD with a 4TX oil tank it seems then. Black/yellow - blue/yellow are from the clutch micro switch. Provided a 3VD pick up coil will trigger a 4TX ignitor unit why not......TPS should be fine.....not sure about the accuracy of the rev counter..


Wife away..can't sleep ..

Edited by Apache, 10 July 2018 - 11:55 pm.