M-Tech problem

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mac
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Fitted a M-tech today and it only retards 3 - 4 degrees,

Set it at 25 deg by timing disc, on checking the timing with a strobe at tick over it's showing approx 22/23 deg and 7/8000 revs it's only retarding to 19 deg. I didn't check the timing with a strobe before I fitted the M-tech :oops:

Indian stator with piaggio pick up and bgm lt coil, ducati cdi, SIl lightened and welded flywheel, all worked fine before set at 18 deg.
earthed the M-tech to the engine casing and cdi earth mount, my normal earths run from the engine casing to strut then to cdi earth mount.

I've read a few different threads where people were having similar problems but couldn't find any solutions.
Last edited by mac on Sat Jul 20, 2013 11:45 pm, edited 1 time in total.
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coaster
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mac wrote:Fitted a M-tech today and it only retards 3 - 4 degrees....... it's showing approx 22/23 deg and 7/8000 revs it's only retarding to 9 deg. .
Your statements seem a bit contradictory :?
mac
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Whoops missed off the 1 should be 19 deg, I should look what I've written before posting :oops:
Minority
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I'm one of "different threads" and have exactly the same problem. Martin at Chiselspeed was great and took the time to test my unit on another scooter and confirmed that the M Tech worked fine with a full 12 degrees retardation.
So it seems that the MTech may be "touchy" about some ignition components, it's just a matter of finding which one(s)!

My setup is:
SIL stator & flywheel (slightly lightened)
Unidentified black CDI
NGK BR8EIX spark plug
Swiss sparkplug cap

As with yours, I experienced no apparent problems with this setup and the timing seemed stable through the rev range when checked with the timing light.

At the moment I have just got a new genuine Ducati CDI and HT lead to try and will get a NGK sparkplug cap and a non-resistor type spark plug (hope it's one of these and not the stator!).
When time allows I will be trying to find if any of these make a difference and I'll report back any findings.

Cheers, John
faf
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have you tried the different settings on the m-tech to see what difference they make?
Minority
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faf wrote:have you tried the different settings on the m-tech to see what difference they make?
I tried all the settings and you could see that there was a difference between the "flat" setting and maximum retard setting.
mac
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Minority wrote:I'm one of "different threads" and have exactly the same problem. Martin at Chiselspeed was great and took the time to test my unit on another scooter and confirmed that the M Tech worked fine with a full 12 degrees retardation.
So it seems that the MTech may be "touchy" about some ignition components, it's just a matter of finding which one(s)!

My setup is:
SIL stator & flywheel (slightly lightened)
Unidentified black CDI
NGK BR8EIX spark plug
Swiss sparkplug cap

As with yours, I experienced no apparent problems with this setup and the timing seemed stable through the rev range when checked with the timing light.

At the moment I have just got a new genuine Ducati CDI and HT lead to try and will get a NGK sparkplug cap and a non-resistor type spark plug (hope it's one of these and not the stator!).
When time allows I will be trying to find if any of these make a difference and I'll report back any findings.

Cheers, John
Hi John,

Similar setup to yours
Br8EIX plug
NGK rubber LB05EMH plug cover

Checked the timing without the M-tech connected and it's 25 degrees, put the M-tech back on and it's about 23 deg and retards to about 19 deg.

I've fitted a couple of M-techs and augustos before and they've used resistor plugs, ducati cdi's, sil and bgm stators.

I'm going to take it off and have a play around when I've got more time to see if I can find whats causing the problem.

Faf,
I tried different settings and you could see a difference in the amount it retarded but because the movement is so small even on the F setting it wasn't much.
mac
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Tried one at a time a B8 plug, different type of ngk plug cap, ht lead, new Ducati cdi added extra earths and it makes no difference.

On the 0 setting there is only about 1 degree of difference over the rev range, on the F setting it's about 4/5 degree, both start at 22/23 degrees even though the static is 25 degrees.
Minority
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mac wrote:Tried one at a time a B8 plug, different type of ngk plug cap, ht lead, new Ducati cdi added extra earths and it makes no difference.

On the 0 setting there is only about 1 degree of difference over the rev range, on the F setting it's about 4/5 degree, both start at 22/23 degrees even though the static is 25 degrees.
Oh dear, does that mean it's the stator or flywheel?

I really hope not. :(

May get a chance this weekend to duplicate your tests (I don't have a spare flywheel or stator to swap).
speedy
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This is of no help whatsoever.....But I just love the word Retardation! Makes me chuckle. :lol:
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