Crankshaft Truing & Tuning

At Scooterotica we can use our 10 tonne hydraulic press to split your crank and rebuild to a high spec. Jap rods and race bearings can be fitted, pins TIG welded, and cranks balanced and trued. The crankshaft is right at the heart of your motor, so any misalignment in the webs, loose pins or weak components can result in the whole engine locking up and will make for a costly rebuild. Always consider crankshaft truing as a minimum when rebuilding your engine or fitting a new kit. And if you are looking at anything above a standard type cylinder kit, then decent big-end bearings and rods must be used, we like to weld the pins to complete the build on all high-performance motors.

 

Below MBD LPC Crankshaft on the tru-stand to check for runout.

 

As always with MBD components, this crank is well within tolerance levels.

 

Full circle 60mm crank with welded pin being checked.

 


 Cutting & Tuning Cranks

There are many reasons and many ways we can tune your crank for you, from the basic tru and rebuild described above, right up to machining and cutting the webs. It maybe that you want and LPC web for your tuned lambretta, or that you need increased inlet timing on your cut-crank for a tuned Vespa, or that you want the full 360 theoretical inlet timing of a reedvalve and the webs need to be flowed accordingly (see here for an article on Vespa reedvalve tuning: Click Me! )

So whatever you require for your crankshaft rebuild/tru/tune we can accommodate your needs. 

 

Lambretta Race Crank from MBD with LPC webs and Jap rod 

 


 

 

MBD Full Circle Alpha Crank in situ... 

 

 

We machined the crank below, it was an AF Rayspeed Race crank, but we cut it down for use on one of our high-power LPC motors. 

 

 

Another version flowed for a long-stroke motor, very smooth.

 


 

 Crank in situ

 

 

 Our workshops are based in Ripon, North Yorkshire, so to make a booking with Scooterotica, or to discuss options either phone Dan on: 07534 375 813 or email: drunkmunkey6969@yahoo.co.uk or Sean on: 01765 690 698