So the build begins!
I have been wanting to undertake another project since the TA replica I took on over three years ago, this is due for its final commissioning at the end of this month where it will be put through its paces on the dyno (worried face!)
Since I began the TA125 build, I have become fascinated by the world of 70s race bikes, the history, stories and machinery of that era are very intriguing. This led me on to discover a machine which I did not know a huge amount about, of course its roots are from the CB750 a bike in itself has left a very prominent flag in motorcycling.
The CR750
A beautiful build of a previous replica, used for inspiration!
To be honest at first the CR750 appealed to me completely on an aesthetic level, just look at it! The lines of the pipes, the tank, the fairing lines and the stance of the bike. This winning the Daytona ridden by Dick Mann in 1969 must have been an incredible sight.
To cut a long story short, I want to build a replica. This will by no means be an "unlimited budget" replica, alike some bikes that have been built. But it will aim to be as "accurate" as the budget allows, fabricating and sourcing replica parts as I go along will hopefully keep the budget on track.
I had anticipated that this build was going to have to happen some time ago, when I decided to place a deposit down on a fuel tank. Having previously constructed the replica tank for my TA125, I contemplated fabricating a tank for the CR replica however after seeing ASA MOYCE'S beautiful work, he was the only man for the job. Last year I paid a deposit in order to be on the waiting list, of which the build slot is slowly approaching around July.
After committing to the project and a fuel tank I then needed to source a bike! If any forum member happens to have this kit of bits boxed up in the loft, please get in touch
After many weeks searching around and bidding on bikes which went way out of my budget, I decided to price up building the CR750 "basis" (CB750 rolling chassis + engine) from parts. This came in at about the same cost as some of the project bikes. I generally have the attitude that some original bikes with patina should not be modified, so could not face "cutting up" a good one.
I searched and searched, and ended up buying a CB750 K4 USA import, this had; non-standard pipes, different forks, repairs needed doing to the frame and crankcases, a few modifications. But all in all a fairly original bike which I could face stripping for the starting block of the CR build. I stripped the bike one Saturday, and all of the parts that were not required (most of the bike) were sold off online, mainly to members of the Honda forums.
This made the "donor bike" a little more affordable. I intend on fabricating my own replica parts that I deem to be too expensive from some suppliers, and using other fantastic suppliers for accurate components such as the tank and exhausts.
There is a huge amount of information out there regarding the CR750s, I have found out more information on the CR750 in one evening than even exists on the TA125 so I feel that although this build is larger and will cost a lot more than the TA, the information and fellow enthusiast group will be a great help. I have been emailing a few different experienced builders of these machines, some of which have been extremely helpful so far so thank you guys it's much appreciated.
The donor bike in all its glory, what a beast of a bike!
CB750 K4:
Now stripped to leave the rolling chassis:
During the strip down I was very pleased with how everything has come off of the bike, and how original the bolts and small components have been, which will hopefully be reflected inside that big engine.
Of course there are a few hurdles:
- the chain has damaged the crankcases at some point in the past and this has been repaired with epoxy (will be cleaned, dressed and delivered to a local master aluminium welder!)
- Some cowboy repair merchant was seeing double when fitting a side stand in the past:
But all in all I feel that it should make a good basis, and as some of you may have noticed, the front end has previously been swapped for an earlier set-up. There is no sign of accident damage to the frame. However this is another reason I was interested in this bike, as I wanted to run the early fork/brake set-up as it is more sympathetic to the original CR look.
I have managed to source the opposing "mirrored" caliper bracket in order to run the dual disk set-up. This is a fairly rough casting but I feel it will clean up relatively well. This will allow me to mount the "original style" CR front mudguard to the bike. As fork stanchions are relatively easy to get hold of I will be replacing these with pattern ones.
However I am still on the lookout for a second caliper. And some drawings/measurements for a CR mudguard.
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I will be documenting the build of this bike in two locations. On the air-cooled RD forum (where the TA125 replica build thread is) and on the SOHC HONDA U.K forum.
I received a huge amount of advice from the members of the air cooled Rd forum and if it is welcome on the forum I would like to keep people posted on the "next project" (apologies it is not a YAMAHA!)
I think that is enough rambling for now, here goes another long build
I can't wait!
All the best,
CR21/RD17
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