Author Topic: rev counter  (Read 14834 times)

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mintex

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Re: rev counter
« Reply #15 on: March 26, 2015, 11:12:53 PM »
Many years ago I did try fitting a Rev counter to a BIS. It does work but it reads twice as fast because as Keith just pointed out the coil fires twice. So for instance it was ticking over at 750 rpm but showing 1500rpm and when I was on the move It was like I was driving a civic type R doing 8000 rpm down a motorway  ;D



If that's the case if you buy a universal tachometer and set it to 4 cyl it should read correct :$

This one i bought (it should arrive tomorrow) says it will run on a 4 cylinder so i can test that theory   :thumbup
« Last Edit: March 26, 2015, 11:14:24 PM by mintex »
Dave

mintex

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Re: rev counter
« Reply #16 on: April 12, 2015, 07:18:30 PM »
i did have a go with that rev counter but i cant get it to read right as yet sadly  :(
With the coil firing both cylinders at the same time would one of a single cylinder bike do the trick?
Dave

mintex

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Re: rev counter
« Reply #17 on: May 08, 2015, 12:43:30 PM »
Any one got any more advice as to fitting a rev counter to a bis. Its a bit or a pain with it having the wasted spark coil were both plugs fire at the same time.

I have one of these just to check the revs when setting the timing and things, it was of an old 2 stroke single cylinder motorbike and it does work ok but it has no light and its battery operated but the battery, i fancy something a bit more permanent 

http://www.ebay.co.uk/itm/LCD-Hour-Meter-Tachometer-Motorcycle-Boat-Gauge-ATV-Engine-Counter-Resettable-UK-/390721988794?pt=LH_DefaultDomain_3&hash=item5af8d868ba
Dave

Mics126

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Re: rev counter
« Reply #18 on: May 09, 2015, 05:37:00 PM »
the fact that you have a wasted sprk ign. coil is irrelevant to any normal rev counter because they use the points to give a signal to the rev counter.

the only thing you do need to try to do is get a two cylinder four stroke revcounter which is hard to get but possible, i got mine from ebay fairly cheap for what it is.

mintex

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Re: rev counter
« Reply #19 on: May 09, 2015, 05:46:40 PM »
ah ok cheers
i do have one for a 2 cylinder 4 stroke engine but i got false reading from it when i tried it? It has 2 selectable switches on the back so maybe i had the set wrong? i will try it again and let you know how i get on.

How have you wired yours in please and is yours a bis  :)
Dave

Mics126

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Re: rev counter
« Reply #20 on: May 09, 2015, 06:14:44 PM »
no mine is a 650 aircooled but its a 1987 one so it has the wasted spark ign. coil. literally you get the feed/signal from the wire between the negative side of the coil to the points on the dizzy (take it from which ever end is easiet for you).

mintex

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Re: rev counter
« Reply #21 on: May 09, 2015, 07:09:47 PM »
Ive just tried it again and im beginning to think this rev counter i have does not work with a 2 cylinder?

This is my battery one and the gauge i was trying to fit and as you can see (they were both fluctuating a bit) the gauge is reading nearly double  :cry:

« Last Edit: May 09, 2015, 07:12:58 PM by mintex »
Dave

mintex

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Re: rev counter
« Reply #22 on: May 10, 2015, 12:10:17 AM »
Ive just found this on blitzracing for the bis.

Quote
Its not that easy to find an aftermarket rev counter for a 2 cylinder engine , so out with a soldering iron to modify one. The unit I used had a switch on the rear for 4, 6, or 8 cylinders.  Each switch setting was fed from a resistor, that simply changed in direct value to the number of cylinders. The 4 cylinder value was twice that of the 8 cylinder ( and the 6 being 1.5 times  ) , so I used a couple of resistors to make up  twice the value of the 4 cylinder to make it work for 2. The value needs to be kept accurate to keep the calibration of the gauge . I have also fitted a motor cycle rev counter (MZ Scorpion 600cc single) that simply had an adjustment on the rear that can be tweeked to work on the twin cylinder engine. It should be possible to use rev counter from Twin cylinder 4 strokes or single cylinder 2 strokes for 1 spark per revolution.  
« Last Edit: May 10, 2015, 12:12:41 AM by mintex »
Dave

Mics126

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Re: rev counter
« Reply #23 on: May 10, 2015, 02:33:05 PM »
that would work too. i will look at mine tommorow to see what make it is.

mintex

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Re: rev counter
« Reply #24 on: May 10, 2015, 07:51:15 PM »
Ok, thanks mate  :good:
Dave

Franck14

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Re: rev counter
« Reply #25 on: May 12, 2015, 12:59:42 PM »
I've fitted a BMW R75/7 rev counter to mine. Cheap at bikejumbles, works fine, and nice to look at. Needs a bit of work though and needs a box from another counter (Jaeger, V├ęglia, Smith, what so ever in 80 mm) to fit in

mintex

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Re: rev counter
« Reply #26 on: May 12, 2015, 10:52:29 PM »
Ah thanks Franck, that's another option for me to look at  :good:
Dave

Mics126

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Re: rev counter
« Reply #27 on: May 13, 2015, 10:12:06 PM »
i couldn't find the make of my rev counter on it. its probably on the box which is hard to find.

mintex

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Re: rev counter
« Reply #28 on: May 13, 2015, 11:28:30 PM »
Ah ok bud, thanks for looking  :good:
Dave

mintex

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Re: rev counter
« Reply #29 on: May 21, 2015, 10:17:46 PM »
Its a bit expensive really but i wonder if it would work? Be nice if it would as i like them better than digital ones.

http://www.ecas2cvparts.co.uk/tachometer-counter-52mm-diam-silver-bezel-white-face-engine-8000rpm-p-1964.html
Dave

 

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