Racing a 3EN2

[Kayla850]

So from my really ruff reading its restricted in nuetral and when the speedo is 0?

If thats the case can you measure the reading from the speedo wire stood and moving and disconnect the neutral switch?


Or am i missing something???

Cheers
Ian

There is no restriction at rest (neutral) ...

In neutral or at rest the bike will rev till the engine rev limiter engages circa 14500/15000 .(or go bang)
This makes for difficult diagnosis; you do not want to be doing road tests with engine at 12,500 + even with clutch pulled in !
The neutral switch has no influence on the circuit. (as Kayla has discovered. )

I thought that too, which is why I did this test-

Neutral switch bypassed (ie the bike thinks it's in neutral all the time, even in gear and moving)
Speedo cable removed so the needle stayed at zero mph and gave a continous 'on' signal to the ignition (ie the initial switch on condition)
Speedo wiring plugged in

to simulate the bike being in neutral and being revved to the limiter at a standstill.

The bike still would not pull past 12,500 in first or second, but in neutral as far as the ignition was concerned (rolling, clutch in and slowly winding it up to the limiter)

The ignition needs an 'on' signal from the speedo and an 'off' signal as soon as the bike moves off from a standstill to run normally. No 'off' signal, regardless of whether the bike is in neutral or not (it seems) leads to the rpm restriction.

[Morespeedvicar]

Hi, the sensor is a opto there and ir led in one side and a photo transistor in the other, like they use in old school ball pc mouses. i'll have more of a read later on. It must just be outputing a high or low signal, If i wasnt so far away from everybody i'd have a play, its easier to do stuff when its in front of you.

Kayla you good with a multi meter?
Can you power up the circuit? Prob best to measure the voltage to the ign wire first its prob 12v but could be 5v, or just plug it back onto the bike, then measure the volts on the outputs between them and ground, then put a peice of card or plastic between the opto and measure them again. this should give you a reading of what is doing and a start of how we can emulate it?

Cheers
Ian

[Kayla850]

Hi, the sensor is a opto there and ir led in one side and a photo transistor in the other, like they use in old school ball pc mouses. i'll have more of a read later on. It must just be outputing a high or low signal, If i wasnt so far away from everybody i'd have a play, its easier to do stuff when its in front of you.

Kayla you good with a multi meter?
Can you power up the circuit? Prob best to measure the voltage to the ign wire first its prob 12v but could be 5v, or just plug it back onto the bike, then measure the volts on the outputs between them and ground, then put a peice of card or plastic between the opto and measure them again. this should give you a reading of what is doing and a start of how we can emulate it?

Cheers
Ian

Hi Ian,

Our multi meter is a bit pants but the voltage across the brown and black wires looked to be 12V, with the voltage across the outputs and ground at around 5V or so.

Bike's for sale now, I just cannot be bothered any more.

[willandrip]

Here endeth todays lesson..........

[Kayla850]

Here endeth todays lesson..........

How did you get on with the M-max on yours today Bill? If I could find one (and I've PMed Levo about his spare) or Ignitech would deign to answer their f-ing emails about the dodgy box they sent me, I'd probably keep the bike. As it is, it's a waste of time trying to run a race bike that won't run right so I might as well sell it in road trim with the gold converter fitted (which, ironically, will be faster than it is as a race bike!)

[Evilchicken0]

If a bike's on the dyno you run the speedo off a drill so the CDI thinks the bike's moving.

Kayla - You want a M-Max ?

[Kayla850]

Kayla - You want a M-Max ?

If you've got one spare Boris, yes please.

[willandrip]

Right then;
Was in the process of doing an update when notifications came in of 3 for sale threads on 2 different forums.
Did not wish to vex you further so I STFU.

Update
The 32 bike has coughed and spluttered at around the 12.5 K mark since it was finished.
Carbs were clarted on with,105/107.5 mains to suit the Cobra system fitted and tubes and needles swapped.Fuel heights were varied.
The ignition side was checked out,so was the V/R, harness and battery.
It has a converter fitted and all speedo wires showed continuity.
I still put it down to a restriction circuit fault.
Fitted the M-Max behind speedo.
This was 2 months ago and had no time till today to test.

Test results today;1300 hrs> no wind >circa 27. C

Bike will rev cleanly to well in of excess of 15.5 K in all gears (has something like 16/47 gearing) 2.94:1 ratio
Whittonstall bank from Ebchester,a 1:4 2 mile straight climb was summited at 115 on speedo from stationary (112 actual with the GPS speedometer)W.O.T
The back straight from Allendale to Hexham racecourse, a 3.5 mile slighly downhill section, showed a speedo reading of 135+
(actual was 131 with a quick glimpse at the GPS) Rpm was circa 15 k.> 12.5 st.rider fully tucked.W.O.T.

Test complete.
May try to lower fuel level 0.5 mm as it still felt somewhat enriched and air temp is well above average.

Conclusion.
An unknown fault in the speedo restriction circuit has been diagnosed via the use of the derestriction box.
Replacement instruments will be sourced and fitted at will.
A 46 tooth rear sprocket is in stock for gearing alterations.
A dyno run is envisaged with Paul Gowland (Allendale).

[Kurlon]

Kayla, looks like someone's trying to solve your issue:

http://fzronline.com/forum/viewtopic.ph ... c3611c8fd5

[willandrip]

Kayla, looks like someone's trying to solve your issue:

http://fzronline.com/forum/viewtopic.ph ... c3611c8fd5

Oh;trust someone to go and spoil it; this was mean to be a suprise
A thread from 2009 had to be resurrected first; plus some coaxing;
http://www.fzronline.com/forum/viewtopi ... 8&start=15.
Turns out it may not be needed for the intended recipient as a M-Max has been very kindly sent by a highly respected member on here,
The work will continue though and as a bonus; another of our members Ian (Morespeedvicar) has also picked up the ball.

In our next enthralling episode; Will Kayla be brave enough to open up the box and disassemble to finally work out how they operate and how easy it will be to copy the components ? (I sure ain't on mine )

And to think ;that bike was nearly up for sale not two days ago !!

I'll get my coat .