Author Topic: Witt Boxes - Cool or No?  (Read 734 times)

Online Paul H

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Witt Boxes - Cool or No?
« on: July 09, 2019, 19:52 »
I'm running a Dmc2 and it's underseat position is surrounded by toolwraps, spare bulbs snd all the other crap we 'enthusiasts' have to carry.

 Infact there is a piece of foam against the side of the dmc2 box to stop toolwraps clanging into it.

Last night I had to get the tools out and noticed the box was warm. Not hot, but bloody warm. OK, I had been running in 35 degree heat all day, but was surprised how warm it was.

Could heat have contributed to Al's failure during his breganze visit?  Do they need air over them?

I'll email Uwe when I get home, but wondered if there was any knowledge out there.


Offline Rob

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Re: Witt Boxes - Cool or No?
« Reply #1 on: July 09, 2019, 21:38 »
The original instructions did specify not exposing the unit to extreme heat e. g. fitting above the engine. So best to leave the box unencumbered. Details here on p3...

Having said that, proximity to HT interference was/is more of a concern, as is a decent direct connection to battery negative.

I've suffered problems with the later silver label DMC 2 and latest DMC 32 on my RGS. Both tested by Uwe and no fault found. An earlier red label DMC 2 unit works fine (thanks Red). Keith now prefers the Ignitech option.

The DMC 2 units on my 750 and old RGS work well!

Maybe stay with points....  >:D

Offline Laverdalothar

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Re: Witt Boxes - Cool or No?
« Reply #2 on: July 10, 2019, 09:40 »
I have both my Jota and my 1000 SFC running the DMC (Jota DMC 1.1 with the blue box, 1000 SFC with the 2.0 and brown box). I even had a 1000 SFC with the 1.0 (silver box), still running fine. All 3 systems have covered around 30.000km or more absolutely faultlessly in 20, 30 or more years.

The main reason when these systems show a fault is mostly a bad cable connection or - on the DMC 1.0 and 1.1 - bad insulation of the cables comming from the original pickups.

On the DMC 2, the large connector on top is known to have broken connections on the cable side. This can be prevented by the right routing of the cables.

Overheating can be prevented by mounting the box f.e. on the same holder as the regulator/rectifyer. Typically, there is an air-stream that cools the regulator/rectifyer, so there should be enough air also to cool the DMC, I assume...
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1000 SFC 1985 #2934 currently under restoration
1000 SFC Preproduction bike 1985 #0001 *sold*
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Offline RCGBOB44

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Re: Witt Boxes - Cool or No?
« Reply #3 on: July 10, 2019, 23:54 »
If its of any help I mounted my DMC box behind the battery tray/box
My Jota goes rumpety rump!
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My KTm goes bang bang bang

Offline ghwallice

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Re: Witt Boxes - Cool or No?
« Reply #4 on: July 11, 2019, 22:40 »
If its of any help I mounted my DMC box behind the battery tray/box

That's where I fitted mine on the 3CL, and it's also where I mounted the Ignitec, which I prefer, on my other 3CL
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Online Sir Sidney Ruffdiamond

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Re: Witt Boxes - Cool or No?
« Reply #5 on: July 12, 2019, 16:36 »
Could be Shauns downfall on the sprint on Wednesday  - it was warm - no doubt we will find out