Dominator rev counter drive

Hello -

Norton did not make a rev-counter drive, Smiths did , But not for the model 99. You will have to get a timing cover from a 650SS, and Norvil Motorcycles or RGM Motors, do the rev-counter the drive gear, and cable if you need one and there a bracket for the top fork nut that fits on the right hand side, the cost of around £350 for the lot, maybe a bit more than that, Hope this may help

Previously wrote:

Hi.

Itâs not often I disagree with Anna, but, Norton did list a (Smiths) rev counter anddrive for the 88 & 99 which had to be ordered as âOptional Equipmentâ. Please see attachedfile from the 59 parts list. From the part numbers it looks like Norton were using up their stock of rev counters left over from their early post-war Manx models. The rev counter drive was the early brass type which are really hard to get hold of and, as they were fitted to the Manx, go for silly money but the ones supplied by RGM will suffice.

Incidentally, my own 1958 99 (my late Fatherâs which has been âin the familyâ since 64) had a rev counter fitted to it, when he bought it, using the âstandardâ timing cover with the small oil pressure release valve. The point where the rev counter drive was fitted was neatly built up with weld and then machined off. It was used with a combined speedo/tacho from a H**da CB450 which meant the speedo was way out. The Norton âoptionâ would have had the larger type oil release valve as found on the earlier Dommies and on the 650SS as Anna says. However, modifying the existing cover as described above shouldnât cause any problems if itâs done right.

Does anyone know why they change the oil pressure relief valve design and then changed it back again?

Regards.

Ian.

Hello Ian As I said Norton did not fit revcounters They were optional extras and fit by the shop or whoever bought the machine. A 2:1 ratio Smiths recounter RC1300/02 or RC1309/00, will cost around £350 for the clock - if you can get one, the mounting bracket is £59. The drive cables are about £30 and the Gear drive of the end of the Camshaft is about £180. (Bg508/06 if you can get one ). Best of get the later type 4:1 and they're avalable from RGM.Motors or NorVil Motorcycles.

Speedograph Richfield do rev counter drives at good prices (at least last time I looked at their website) - also excellent speedo & rev counter cables. When I was an impoverished student, we would take standard timing covers and build up the rev counter boss using araldite or plastic metal then with a bit of drilling and shaping have a perfectly acceptable rev-counter timing cover. Easy... Ideally you should fit a Smiths Chronometric but most people fit a Smiths magnetic. Much easier to fit a 2:1 r/c gearbox and have a 4:1 rev counter as the 4:1s are more common.

Just to say there is a 'mounting kit' on E-bay (£14 at the mo' and no bids so far, finishing this evening) for a 500T which is much the same as the Manx/Dommi option listed in the 59 parts book. Not sure whether a magnetic tacho would fit itthough. If you do want to go the orig-anal Manx/Dommi route Stu Rogers does these parts too.

Cheers.

Ian.

Previously wrote:

Hello

Does anyone Know the best place in the UKto get a rev counter drive assembly (the part that sits on the timing casing and is driven of the camshaft)for my norton dominator model 99?.HaveI alsogot to get a certian typeof revcounter driveor did norton only make one type for the dominators?

Thanks

Hello Alec

You Can get a electronic Rev-counter at work of you coil or magneto for about £130 from Mick Hemmings ? hope this helps ?

My Mercury came standard sans rev counting. I really did not want to have an unsightly cable protruding from the timing case so installed an electronic unit I purchased from a US Harley customising intenet shop. I am using a Boyer electronic ignition which give the pulse required for twin cylinder rev counter. All stainless and clamps to the bars per attached pic.

Previously wrote:

Hello

Does anyone Know the best place in the UKto get a rev counter drive assembly (the part that sits on the timing casing and is driven of the camshaft)for my norton dominator model 99?.HaveI alsogot to get a certian typeof revcounter driveor did norton only make one type for the dominators?

Thanks

Try Gaggs of Nottingham, as they do a huge amount of Smiths replacement Speedo drives, cables and revcounter drives. The revcounters fitted the 1950's Dominators is an intersting subject. While i was at Kempton Park this year, a dealer had a timing cover with a revcounter boss cast into the cover, on his stall.The intersting part was that the timing cover also had cast into the cover a recess to take the round Norton badge that was fitted on the timing covers of the 1950's Norton twins. It did not cost me that much, and it may have been a optional extra that may have been fitted to either the 88 or 99 models, or even the earlier Manxman models from 1960 to 1961. It was such a surprise to see this item i just had to buy it. There really is no common sense when it comes to buying bikes or their related parts.

Previously wrote:

Previously wrote:

Hello

Does anyone Know the best place in the UKto get a rev counter drive assembly (the part that sits on the timing casing and is driven of the camshaft)for my norton dominator model 99?.HaveI alsogot to get a certian typeof revcounter driveor did norton only make one type for the dominators?

Thanks

Try Gaggs of Nottingham, as they do a huge amount of Smiths replacement Speedo drives, cables and revcounter drives. The revcounters fitted the 1950's Dominators is an intersting subject. While i was at Kempton Park this year, a dealer had a timing cover with a revcounter boss cast into the cover, on his stall.The intersting part was that the timing cover also had cast into the cover a recess to take the round Norton badge that was fitted on the timing covers of the 1950's Norton twins. It did not cost me that much, and it may have been a optional extra that may have been fitted to either the 88 or 99 models, or even the earlier Manxman models from 1960 to 1961. It was such a surprise to see this item i just had to buy it. There really is no common sense when it comes to buying bikes or their related parts.

Hello yes the Norton Manxman was the first Model to have a Rev counter fitted as Standard And Chromed Mudguards And Slim 2.1/2 gallon Tank. As well as twin carburetters and a High lift camshaft flat type followers and, The fat type push rods the same ones went into the Atlas and Commando . later on They got called the SS cam . And they had A Very Nice paint job in Polychomatic Blue top of by a Nice Bright red seat with white piping round the edges . what a Nice looking Bike they where . And very nice Machine to ride , had more power than the Bonnevllie At that time with 52bhp on tap and you would see 120mph on the speedo at top speed . Extreamly Rare Now, But I have One from the First 300 Batch sent too the USA .You will see it at The NEC on The Norton Stand .

There must have been two of those timing covers at Kempton Park, as i bought a timing cover with the boss for the revcounter, and the round raized casting part for the round Norton badge that recesses into the centre of thetiming cover. I was going to use if for my Manxman engine, as this timing cover has the revcounter boss at an angle on this cover. I bought it at the time as i had never seen one before. The earlier timing covers had the pressure relief valves internally in the cover, and the other one had the complete unit screwed into the cover. The workshop manuals explain all this as well as the Norton histories out there.

Previously Gordon Johnston wrote:

Ideally you should fit a Smiths Chronometric but most people fit a Smiths magnetic. Much easier to fit a 2:1 r/c gearbox and have a 4:1 rev counter as the 4:1s are more common.

Just to clarify, having pored over this thread, and others, does the Smiths magnetic rev-counter RSM3003/00A require a 4:1 gearbox? I don't quite understand what is written here; 2:1 gearbox, 4:1 rev counter?

The camshaft runs at half engine speed, so with a 2:1 gearbox drive yourratio to the rev counter is 4:1, hence a 4:1 rev counter.

The standard set up is a 1:1 gearbox with a 2:1 clockwise rev counter. I am fairly certain you can't get a 4:1 gearbox.

Thanks Gordon. The problem with my 650ss is that, when I bought it, aftermarket clocks had been fitted, the rev-counter of which I understand is a 4:1 item. It worked ok, but I eventually stumbled across a pair of original correct grey face items. I sent them off for refurbishment, and have just fitted them. The speedo is way slow; it needs a 2:1 drive, the aftermarket one running off a 15:12 drive. No probs, throw a bit more money at it for the correct drive, problems should be sorted.

The rev counter, however, will barely struggle up to an indicated 1500rpm, Swapping back to the cheap one restores accuracy. As it appears that they both should be 4:1, then it cannot be the drive gearbox at fault. I am now wondering if the chap who refurb'd the magnetic one has calibrated it incorrectly. I remember him saying it was way out of calibration, which is not what he expected to find....

btw, you mentioned earlier in this thread that Speedograph Richfield supply drives, well they still do, from 1:1 through to 8:1, and by today's standards, reasonably priced ....

http://www.speedograph-richfield.com/html/rgb1507_1508_series.html

Ian

The revcounter drive is a BG1508/05 and it is a 1.1 drive with a 2.1 revcounter instrument. The BG1508 gearbox reverses therotation of the shaft that they are attached to. To solve your problem buy a 1.1 drive with a 2.1 Magnetic revcounter and this should solve your problems. The only problem with the Smiths drive is that they shed their pushed in discs and the drive gear falls out.The pattern recounter drivesthat are sealed, but theywill leak, past the timing cover and the top of the revcounter cable screw on nut.The designation /5 is the depth that the recounter fits into the timing cover. The post 1964 Atlas, 650,and N15 revcounter assemblies are all the same but the recounter cables are of different lengths.

Previously anthony_curzon wrote:

The revcounter drive is a BG1508/05 and it is a 1.1 drive with a 2.1 revcounter instrument. The BG1508 gearbox reverses therotation of the shaft that they are attached to. To solve your problem buy a 1.1 drive with a 2.1 Magnetic revcounter and this should solve your problems. The only problem with the Smiths drive is that they shed their pushed in discs and the drive gear falls out.The pattern recounter drivesthat are sealed, but theywill leak, past the timing cover and the top of the revcounter cable screw on nut.The designation /5 is the depth that the recounter fits into the timing cover. The post 1964 Atlas, 650,and N15 revcounter assemblies are all the same but the recounter cables are of different lengths.

Hi Anthony,

Can you give me some more details on the designation /5 measurement?

How is the measurement made with respect to the timing cover?

regards

Having just checked, my drive rotates 1/4 turn per engine revolution, so a 2:1 drive, correct for my aftermarket 4:1 clock.

If I am correct in thinking that my RSM3003/00A is 2:1, then, as Anthony states, I need a 1:1 drive gearbox, which appear to be available from Speedograph Richfield.

My only question mark before ordering is that my engine is also fitted with one of these modified timing covers, as you have described, Anthony. Is there any possibility that depth, as per the /05 designation, could be different from an original rev-counter drive timing cover?

The revcounter drive is a BG1508/05 and it is a 1.1 drive with a 2.1 revcounter instrument. The BG1508 gearbox reverses therotation of the shaft that they are attached to. To solve your problem buy a 1.1 drive with a 2.1 Magnetic revcounter and this should solve your problems. The only problem with the Smiths drive is that they shed their pushed in discs and the drive gear falls out.The pattern recounter drivesthat are sealed, but theywill leak, past the timing cover and the top of the revcounter cable screw on nut.The designation /5 is the depth that the recounter fits into the timing cover. The post 1964 Atlas, 650,and N15 revcounter assemblies are all the same but the recounter cables are of different lengths.

The correct revcounterr drive to go with the Magnetic head is a BG1508/05, and will fit the Norton timing cover.The /05is the depth of the ridge on the revcounter, and it fits in the ridge on the revcounting timing cover.This is as per the Smiths books, and all the later Norton twins used this drive. The revcounter cable should have a metal sheath at the bottom to stop the cable being burnt on the exhuast pipe if you use the slooping revcounter timing cover. It you use the later straight up type timing cover you should still use the heat shielding at the lower part of the cable.

That's great. Thanks for all the info. I will order up the drive. I have the correct cable.

The correct revcounterr drive to go with the Magnetic head is a BG1508/05, and will fit the Norton timing cover.The /05is the depth of the ridge on the revcounter, and it fits in the ridge on the revcounting timing cover.This is as per the Smiths books, and all the later Norton twins used this drive. The revcounter cable should have a metal sheath at the bottom to stop the cable being burnt on the exhuast pipe if you use the slooping revcounter timing cover. It you use the later straight up type timing cover you should still use the heat shielding at the lower part of the cable.

yours anna j