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Intermediate timing gear, dynamo Dommie 99

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I have a 57 dominator 99 which may have the wrong intermediate timing gear/sprocket fitted, can someone kindly give me some guidance . In the WC Haycraft book on dominators in suggests two methods of fitting timing sprockets and chains, one for 55-57 dynamo models and one for 58-65 model. the first states that when the teeth on the half-time pinion and intermediate gears are aligned the marked tooth will be at the top. On the second instruction (58-65) states in this position the marked tooth will be at 11 o'clock. This suggests the intermediate gear is marked one tooth differently for dynamo models, can anyone tell me if this is the case? do I have the wrong gear fitted?

Many thanks, Steve Coleman

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Hello THIS is Stright Forward Right let start with the crankshaft timing gear with the worm removed you will then see a punchmark in-between the teeth on this gear. this pinch mark need to be at top dead centre from the drive side cylinder or left-hand side and the left-handside valves must be closed are you followingme! Next up you must fit the chain and intermediate gear do not forget the thrustwasher for the intermediate gear and the camshaft gear together in one go over the keyway for the camshaft and have the intermediate gear punch mark looking downward to match up with the crankshaft timing gear punch make they shouldbe opposite each other and punchmarks on the intermediategear where the chain is and the punch mark on the camshaft sprocket should be at 11 o'clock and all this should be fitted in one go all together to ensure you have the right valve timing and ignition timing with this all in place you can then do you ignition timing and on a modle 99 it will be 32degees before top dead centerstatic timing and always time your engine from the drive side or left-hand side has this is cylinder number one,. on a magneto or distributor the number one lead in the one nearest to the battery box now read careful and have fun with it , yours anna j

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Hello please make a note a single cylinder engine only fire's once every 720 degrees or two turns of the crankshaft, Now a twin cylinder engine fires twice in every 720 degrees or once in every 360 degrees have you all now got it in your heads well have fun with all this yours anna j

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Previously anna jeannette Dixon wrote:

Hello THIS is Stright Forward Right let start with the crankshaft timing gear with the worm removed you will then see a punchmark in-between the teeth on this gear. this pinch mark need to be at top dead centre from the drive side cylinder or left-hand side and the left-handside valves must be closed are you followingme! Next up you must fit the chain and intermediate gear do not forget the thrustwasher for the intermediate gear and the camshaft gear together in one go over the keyway for the camshaft and have the intermediate gear punch mark looking downward to match up with the crankshaft timing gear punch make they shouldbe opposite each other and punchmarks on the intermediategear where the chain is and the punch mark on the camshaft sprocket should be at 11 o'clock and all this should be fitted in one go all together to ensure you have the right valve timing and ignition timing with this all in place you can then do you ignition timing and on a modle 99 it will be 32degees before top dead centerstatic timing and always time your engine from the drive side or left-hand side has this is cylinder number one,. on a magneto or distributor the number one lead in the one nearest to the battery box now read careful and have fun with it , yours anna j

Many thanks for your prompt reply Anna, I am ok with the assembly process which is currently just as you suggest, my worry is that both the original 57 manual and the Haycraft manual suggest the intermediate gear is different for the pre 58 dynamo bike and when the crank pinion and intermediate gear aligns the sprockets should present at 12,clock and not 11,o'clock. this would suggest that the dynamo models require a different intermediate gear to later bikes, to add to my confusion the club spares list an intermediate gear for dynamo engines.

Are you saying this gear is the same for all models, and I am ok with my 11,o'clock set up?

Thanks again Anna. Steve

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Steve,

The following is taken from Norton by P.L. Garratt.

Fitting timing sprockets and chains. 1949-57 Dominator 7,77,88,99.

Fit half time pinion with the chamfered edge outside and tap home with tubular drift. Fit thin washer to camshaft, followed by spider clutch spring and fit camshaft key. Replace thin washer [ this is thinner than camshaft washer ] to intermediate gear spindle and rotate engine until the marked tooth on the half time pinion is in the TDC position. Rotate camshaft until the keyway is also in the TDC position. Before fitting the chains to the sprockets, mark the tooth on either side of the marked space on the intermediate gear wheel, because when the chains are in position the timing mark is obscured. Place the magneto chain [ the narrower of the two ] on the inner of the two sprockets on the intermediate gear and the camshaft chain on the other sprocket. Rotate the intermediate gear until the marked tooth is in theBDC position. The chains and sprocket assemblies may now be placed loosely in position, the magneto sprocket and ATD mechanism meshed with its driving chain and the whole assembly pushed home checking that the clutch spider spring is located with one leg either side of the friction plate peg. When the half time pinion and intermediate gear are in mesh, the sprockets should be in the eleven o clock position. The valve timing is correct when six outer plates on the camshaft chain separate the marked teeth on the sprockets with the half time pinion and intermediate gear correctly meshed. FOOTNOTE. I have read through the fitting procedure for 1958 on and apart from the distributor as opposed to a magneto the end process is the same ie all pinions in mesh, sprockets at 11 o clock and six outer plates separating marked teeth. Hope this helps, Phil.

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Previously philip_chester wrote:

Steve,

The following is taken from Norton by P.L. Garratt.

Fitting timing sprockets and chains. 1949-57 Dominator 7,77,88,99.

Fit half time pinion with the chamfered edge outside and tap home with tubular drift. Fit thin washer to camshaft, followed by spider clutch spring and fit camshaft key. Replace thin washer [ this is thinner than camshaft washer ] to intermediate gear spindle and rotate engine until the marked tooth on the half time pinion is in the TDC position. Rotate camshaft until the keyway is also in the TDC position. Before fitting the chains to the sprockets, mark the tooth on either side of the marked space on the intermediate gear wheel, because when the chains are in position the timing mark is obscured. Place the magneto chain [ the narrower of the two ] on the inner of the two sprockets on the intermediate gear and the camshaft chain on the other sprocket. Rotate the intermediate gear until the marked tooth is in theBDC position. The chains and sprocket assemblies may now be placed loosely in position, the magneto sprocket and ATD mechanism meshed with its driving chain and the whole assembly pushed home checking that the clutch spider spring is located with one leg either side of the friction plate peg. When the half time pinion and intermediate gear are in mesh, the sprockets should be in the eleven o clock position. The valve timing is correct when six outer plates on the camshaft chain separate the marked teeth on the sprockets with the half time pinion and intermediate gear correctly meshed. FOOTNOTE. I have read through the fitting procedure for 1958 on and apart from the distributor as opposed to a magneto the end process is the same ie all pinions in mesh, sprockets at 11 o clock and six outer plates separating marked teeth. Hope this helps, Phil.

Thanks so much Phil, it seems I am ok with my present set up after all.

I am very grateful to you for taking the time and trouble to get this info to me, I have been looking for some time for a copy of P.L. Garrett,s book as yet with no success, I will continue to look.

Best regards, Steve.

 


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