timing chain

[stuupnorth]

Hi all
Am i right in thinking the 1275 from a midget has a duplex timing chain set up ??
cheers
Stu

[philthehill]

That is correct.
Chain Duplex Pt No: 2H4905
Cam gear Duplex Pt No: 12G1397.
Crank gear Duplex Pt No: 12G1699.

[Chipper]

Does anyone know what the service change interval is on these? I fitted one to my rebuilt Midget 1275 60,000 miles ago, and it shows no signs of rattling so far...

[philthehill]

There is no service/change interval on the duplex set up. When it starts to get noisy and you can feel backlash between crankshaft and camshaft it is time to change the chain and possibly the crankshaft gear. https://www.minisport.com/aea695-steel- ... shaft.html
The crankshaft gear rotates twice as many times as the camshaft gear so is prone to wear. As the camshaft gear rotates at half speed and is considerably bigger in diameter the camshaft gear is not prone to wear. Changing the engine oil on a regular basis prolongs the life of the timing chain and other components.
The steel camshaft gear is Pt No: AEA696 and with steel camshaft gear Pt No: AEA695 they are the best production timing gears available.

[Chipper]

Thanks for the info, Phil.