Correct levers for 1960 Slimline 99SS

Hi Bert,

My 1957 99 has the 1" centres on the clutch and 7/8" centres on the brake.

The 7/8" centres give a better mechanical advantage and therefore more cable pull and better braking.

The 1" clutch increases the force required but gives more cable travel reducing the chance of clutch drag.

Hope this helps.

Dick

My 1960 99 std untill recently had the orriginal levers both non adjustable. The clutch is 7/8th cc which is correct for the AMC box. I had always assumed the brake to be the same but was surprised to find it to be 1 1/16, It is definately orriginal and features the choke mounted on top with the curious extended nut underneath. I have used a 7/8th lever for the brake and find it to give a better action but needing regular adjustment and a good solid cable. I own bikes with SLS and TLS Norton brakes and find that providing I ensure the leading shoe is always the thicker of the two then the SLS brake is as good as the TLS but being less fussy on set up and a bonus is that it will also stop in reverse.Which the TLS will not. What was fitted to the SS models I can't be sure although ball ended levers were common on them.

Previously robert_tuck wrote:

My 1960 99 std untill recently had the orriginal levers both non adjustable. The clutch is 7/8th cc which is correct for the AMC box. I had always assumed the brake to be the same but was surprised to find it to be 1 1/16, It is definately orriginal and features the choke mounted on top with the curious extended nut underneath. I have used a 7/8th lever for the brake and find it to give a better action but needing regular adjustment and a good solid cable. I own bikes with SLS and TLS Norton brakes and find that providing I ensure the leading shoe is always the thicker of the two then the SLS brake is as good as the TLS but being less fussy on set up and a bonus is that it will also stop in reverse.Which the TLS will not. What was fitted to the SS models I can't be sure although ball ended levers were common on them.

hello original leavers were AMAL As I have the Amal Leaver manual yours anna j

For the AMC gearbox, Norton fitted 7/8" clutch levers. The clutch lifter profile on the AMC box is too sharp, so gives lots of lift but is heavy. Using a 1 1/8" lever will make the clutch very heavy indeed.

Paul

Previously paul_standeven wrote:

For the AMC gearbox, Norton fitted 7/8" clutch levers. The clutch lifter profile on the AMC box is too sharp, so gives lots of lift but is heavy. Using a 1 1/8" lever will make the clutch very heavy indeed.

Paul

hello there is a reason why the clutch is heavy you have the wrong clutch springs that are way too strong try getting a set of lighter springs but with the same bite, and the clutch cable end at the gearbox end should have a small ball end and not a nipple barrel end like you get from the after market , its these people that are making parts that are incorrect parts that are not doing the job in the correct way ,So by getting the right cable and the right type of springs for your clutch will make your life and riding that much better yours anna j

Anna raises a good point about incorrect parts. Just because the part has been supplied by a business that professes to know about Nortons does not mean the parts will work on your bike. Clutch springs are a case in point and to tell the diference between right and wrong you will need at the very minimumm a micrometer to measure the wire diameter ,Which will be a good indicator. You will also need the correct free length and some way of measuring the quality of the spring action. Hard springs are not the answer. Room here for an informative technical article.

I expect someone swapped the levers over thinking that the bigger CC would give a bit more travel for a draggy clutch.

Previously Bert Powell wrote:

Many Thanks for all the responses.

Really appreciate you all trying to help me out!

My bike, the one in question here; is a 1960 99SS with 48,000 miles on the clock. I am only the second registered keeper since it was first registered in Feb 1961. It is in very original and unrestored condition. I am trying to retain as much of its originality as possible.

The handlebar levers, and throttle are all marked Doherty items and all appear original as do the rubber grips which have a diamond pattern.

I think the actual lever blades may have been mixed-up as the clutch lever has 1"+1/16 pivot points although it is a left-handed blade. The brake lever has 7/8" pivot points and the blade is upside-down and therefore a left-hand item.

New clutch-plates and springs have just been fitted and the clutch works well, even with the 1"+1/16 pivot point blade.

Anna states above that Amal levers were fitted as original equipment.

At this stage I am just trying to establish the correct parts when it left the factory.

Could Doherty levers and throttles also have been used?

Hello Doherty are Aftermarket goodies or baddies witch ever way you look at it I can give the Amal part numbers if this helps Amal clutch leaver for models 88 and 99 are part number 18/556 and combination leaver for air and the front brake are part number 18/732 and twist grip is part number 16/417, and there pain end leavers NOT ball end leavers with NO adjusters on the leavers Now hope this may help and shed some light on things And one other thing is the Model 99SS was Not produced until 20th of april 1961 So what machine you may have I have not a clue but if its 1960 built then its Not a 99SS as the (99SS) wares the Norton Manxman 650 engine cases and cam shafts and follower and push rods fat type the same as the 650s have As just happen to own a december 1960 built Norton Manxman 650 an export only motorcycle there are only 10 with in this country, yours anna J

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Nice looking bike!

Thats a cracker!, Gen SS or not someone has built a very good looking bike. The colour scheme mimics the later SS bikes from around 62, the early 88/99 SS bikes used the same colour schemes as the std bikes. Usually the SS was marked on the crankcase. I would set the Kickstart back a couple of splines as it will interfere with your boot as it is.The speedo drive is set at a steep angle ,possibly a longer than necessary drive cable has been used. The cable run along the lower frame was correct at that time ,later AMC bikes did it differently. The siamese pipes (with a very nice line) are RGM I think.Love that twin Mono carb set up. Throttle cable looks too long, probably worked fine with the normal std low rise bars. The cylinder head is from an earlier bike say 56/7. Usually giving a slightly lower CR (depending on pistons fitted) and smaller valves. probably a good thing if you want the motor to last.

hello nice looking motorcycle but far from factory standard colour is the wrong and colour of the seat is wrong the model (99) standard were in Norton Grey and Dove Grey and seats were in two tone grey and Chrome mudguards where only available at Norton Bracebridge street out let shop has the standard model had dove grey painted mudguards the twin carburetor set up was first fitted to the clubman model 88 and then model 99 1958/60. So now it looks more like a Plumstead 650ss then a bracebridge street beauty with all the 1960 nice colours they did of that era Not all Norton,s were black and silver from 1958 some where nice post office red or forest green or light metalescent blue now early 1950s and 60s Norton's are getting rare in there standard factory colours all very nice smart motorcycle witch would make any owner very proud to own, and a joy to ride, But anyway its your nice model 99 so enjoy your motorcycle and look after it they not make these no more, that's for shure, Well I am sorry to say I am stuck in the Era of 1945 to late 1962, all Bracebridge Street Norton Motorcycles after this it went pare shaped for me, And 45 years owning Norton Motorcycles and enjoyed every minute and I am hoping there is still a bit more to come, As i love these machines, and I can look at them allday there a work of art and a motorcycle rolled into one So if you need any more help I am not far away yours Anna J Dixon

Many of us converted our standard 99s to look like 650ss models. All the rage when I was a lad. Mine started out as a red and white DeLuxe but now looks like a scruffier version of yours.

Accept that the changes are all part of its history and enjoy your rather splendid looking machine.

Couldn't be absolutely sure, but is that a 1959 cylinder head on yours? Is there ribbing between the rocker spindle covers?

The 90 degree fin below the exhaust rocker plate is the giveaway Gordon. Earlier head or not its a nice mixture.