The Scitsu revcounter is able to be fitted to any machine as it works by counting the sparks on the HT lead.
There are different models available for each application and it is important to be precise about your machine and its ignition system when ordering
I usually stock models with a 10,000RPM rev range but all other options are possible to order
These are recharged from a 12v car or motorcycle battery and will run for 8 hrs at least from one charge. The standard version picks up its signal inductively by simply taping the sensor wire from tacho to the H.T. lead. Removing the dummy jack-plugin the side of the tacho switches the revcounter ‘ON’ Replacing the plug conserves the battery by switching it ‘OFF’.
The Scitsu tacho is the favourite among Road Racers and especially the classic class. All Scitsu revcounters come with a special charging lead. No other lead should be used as damage will occur!
All Tachos come with a three legged mounting bracket and anti vibration rubbers which must be used or performance and reliability will be compromised.
It is possible to order a white faced Scitsu Revcounter but only with 10,000 or 14,000 RPM dials. These are a special order and subject to an extra charge.
The Scitsu Racing Revcounter fitting guide .
If you require help in determining which Scitsu model is suitable for your application, please answer the questions below.
The make, model and year of bike or engine is a good starting point!!.
1. Is your engine two stroke or four stroke?
2. How many cylinders does your engine have?
3. If more than one cylinder, what is the crank angle?
4. Make, model of ignition system ie: “original”, Boyer Bransden, Lucas Rita etc. ?
5. Does your ignition system have a “wasted” spark. IE does it spark on the exhaust stroke as well as the compression stroke? If you have a modified magneto or an after market electronic system we advise you to check with the manufacturer for confirmation.
6. How many HT coils does your ignition system have?
7. If it has one coil, how many leads does it have?
8. What rev range/scale do you require?
Please check the notes below the following fitting table for important, specific relevant information. Indicated by symbols. EG: **, (?), ++ etc.
When we refer to a RED model for example we refer to the I.D.colour code on the back of the revcounter and not the colour of the body or face of the revcounter. All revcounters have black body & face.
|Make of machine – Examples.||Ignition type.||Brand name – examples.||Tacho I.D. colour code.||Popular
per engine revolution.
|Connect tacho to
this number of
HT leads. #
|British 4str singles, B50, B40, B44, Goldstar etc.
(without** wasted spark)
Ducati singles & Ducati 888 etc. 68deg V twins ###.
Ducati / Morini etc ###
|British type 4str singles with magneto.
*V twins with magneto.
Manx, G/Star etc.
|Magneto||Lucas, BTH, Bosch
New BTH FM1R
|British 4str singles , B50, B40, B44, Goldstar etc. & unit twins (360 deg crank) with **wasted spark.
Rotax twin, Guzzi *V twins,
** Ducati V twins with wasted spark.
Some 2 stroke *V twins.
(?)Most Single cyl 2strokes.
**Japanese 4str parallel twins.
**Japanese 4str singles.
|Bosch, Boyer Bransden, Motoplat,
Krober, Lucas Rita.
Ducati / Morini etc
|British twins with magneto and some high energy electronic.||Magneto||Lucas, BTH, Bosch
New BTH FM2R
|Kawasaki triple – 2str
120 deg. 2str triple –
120 deg 4str triple with wasted spark. (firing every 120 deg.)
|Coil or electronic||Boyer, Lucas Rita, Krober||Green||0-10,000
|Honda K4 with Motoplat or PVL (wasted spark).
Japanese 4str fours except V’s & without mag fitted.
Japanese 2str twins: TZ250/350
RD250/350, Banshee etc.
4 cyl 2str TZ50/750. RG500
Hitachi, Lucas Rita, Boyer.Motoplat,
(one from each coil)
++ BSA & Truimph triple & 4 stroke triples with 120deg cranks and non wasted spark ignition.
|Electronic||Boyer, Lucas Rita||Orange||0-10,000
|***180 deg. Twins.
& Nourish Weslake
(Ask for advice. Could be uneven spark interval.)
Vincent V twin with new BTH FM2RV
or electronic enhanced system.
Specific important Notes:
* 1/2 Spark means: 1 spark per 2 rev’s of the crankshaft.
** Wasted spark means – Spark also on the exhaust stroke for 4 strokes and at BDC on 2 strokes. Typical of Boyer.
*** May be uneven interval between sparks. So check with us first.
# Number of HT lead s the sensor lead should be taped to.
## One HT lead from each coil.
### Front cylinder HT lead only.
V – Twins:
The way to treat a V twin is like a single. Take the pulse from just one HT lead, ensuring that the pickup lead is kept well away from the 2nd cylinder’s lead so as not to pick up an unwanted signal.
(?) Some 2 strokes may have a wasted spark.
With regard to Triumph and BSA three cylinder bikes there is some confusion possible as ignition systems are available with different firing sequences, ie:
One spark every two revs for each cylinder which equals one & half sparks pre engine revolution or:
One spark every rev for each cylinder which equals three sparks per engine revolution.
Please ensure that you have the correct information for this.