Sunday, 25 May 2025

WELCOME to my blog about restoring vintage overhead camshaft AJS and Velocette motorcycles

 

Apologies to anyone that has come to this page expecting to see exclusively vintage AJS motorcycles .....scroll down the page a bit and you will find plenty of them. However, I ran out of OHC AJSs to restore and I'm now working on early cammy Velocettes.

In 2023 I started the restoration of 2 early Velocette KTTs plus another Mk 1 OHC cammy special - a few details about each of these bikes can be found here and here

Quite a lot of work has been done on these bikes over the past 2 years and the INDEX PAGE provides links in chronological order of the project so far.

I have 3 rolling chassis up together - see here - many smaller details - saddles, tanks, steering dampers, steering locks etc have been sorted out and clutches, gearboxes and positive stops for the 3 bikes have been rebuilt. The engine of KTT 305 has been completely rebuilt with many new parts and I'm now working on completing the dry build - oil/fuel lines, cables, chains and chainguards etc...


I'll report progress on that soon but, in the meantime, I now have the petrol tank of KTT 581 in my workshop.


Although it wears plenty of its 90 years history it is in remarkably good condition.

I have done some preliminary work on the engine - reported here, but I am not actively working on this project yet - I have my hands full with the existing 3 project bikes. However, I have been able to unearth more of the history of KTT 581 and at least I now have a plan for this upcoming project - details here.

During the last 4 years I have posted quite a lot of information and to aid navigation the "Labels" section on the right side of this page lists the various projects.

The labels marked "INDEX" give a link to a page that provides a complete list and links to all of the separate sub-projects related to that main project.

Alternatively, scroll down this page and see what's here...

When I started this blog I already owned (and still own) a 500cc AJS R10


that I've been riding for many years and wanted an early 350cc bike. I bought one at a Bonhams auction; this is what I brought home....

....a bit of work was needed to bring it back to life 

Full details of the restoration can be found here.

During the restoration of the K7 I figured that I could put an early overhead camshaft Velocette cylinder, cylinder head and cambox onto the crankcases of an AJS 350cc engine from 1931, convert it to chain-driven OHC and make an engine that looks like a K7 but has a Velocette top-end. I had a 1928 350cc AJS sidevalve that I had bought on eBay and used that to create the AJcette ....giving credit to both manufacturers.

It looks pretty similar to the K7 and to demonstrate that there really are 2 bikes, here they are both together.


Details of the AJcette project can be found here.

I have quite a lot of early Mk1 OHC Velocette parts and after completing the AJcette I decided to use some of these to make a replica of a one-off bike that AJS built in 1929/1930 for an attempt on the world speed record. The original is a huge V-Twin beast that started out with a naturally-aspirated engine but, having failed to gain the record, was supercharged ...and again failed. The bike ended up in Tasmania for many years and, after being repatriated to the UK and restored, it is now in the National Motorcycle Museum.

This is what the original looked like:

and this is my recreation.

 

 

Like the AJcette, the V-Twin uses Mk 1 OHC Velocette cylinder components. The full story of how this bike was built can be found in the links here.

There is also a 14 minute edited Youtube summary of how these bikes came about here and a longer unedited version here.

In January 2022 I started the restoration of a 1933 AJS Trophy Model

and this was completed in March 2023.

 

The Index Page for this project can be found here.

I also reported briefly on a couple of my other projects ....vintage OHV Nortons


 and putting a Marshall supercharger onto my 1934 MG PA

 


I hope you find something of interest.