Paul Marcos is a man with a plan. And it’s a plan that’s rapidly coming to fruition. How rapidly? How about a new Dry Lake Racers Australian Club Record. Fast enough for you?
I asked Paul to tell me a little bit more about how it all came to be.
“I want to start by giving credits instead of the traditional thing of doing it at the end of the article.
This crazy idea could not have been possible without the genuine enthusiasm of Paul Rooney in advising on the project and, of course, his remarkable engineering skills.
Mates like David and Alex McLachlan and Jeff Mitchell lending their expertise also made the process of developing the platform for this motor far smoother.
My darling wife Heather’s indulgence kept the money (life blood of the project) flowing.
Thank you all.”
So just what is this machine? What if I told you the engine started life as a humble 1982 BMW r100. But as Paul points out “now not even it’s mum would recognise it, only the case and crank remain original BMW equipment”
The list of mods is extensive. Paul laid out the ingredients for a record breaking blitz below:
- Carrillo rods.
- Rooney heads.
- Rooney cam.
- Moto Israel Pistons.
- Moto Israel cylinders.
- Moto Israel pushrods and pushrod tubes.
- Rooney designed fly wheel (for land speed application)
- Suzuki fuel injection.
- EMS EFI Computer. Fantastic tool for tuning and managing a complicated custom system like this.
A critical factor, adds Paul is that the motor is turned sideways in the frame to convert to belt primary and chain final drives giving easy drive ratio change options and more efficient horsepower transfer. “it gives almost zero extra benefits aerodynamically as it’s virtually the same width”.
This combination results in a motor that revs very freely, is rev limited to 8500rpm for competition purposes but is tuned to run to 9000rpm if the extra revs are required.
“Maximum power achieved on the dyno is 103.5hp at the tyre but this has been tuned back to a steady 100hp at the tyre at 7800 rpm to give a very nice linear power curve that starts strongly at 2300rpm.”
This motor drives through a TT Industries 5 speed gearbox which is a copy of the AMC gearbox usually found in a Norton Commando but the TTI gearbox is properly engineered for positive shifts and to take this level of power.
“All this resides in a custom land speed racing frame by David “Bones” McLachlan and bodywork by me”. And bloody nice work it is.
“Initial practice runs on Lake Gairdner this year showed some very promising signs but disappointingly we developed a mystery misfire which I believe was due to low battery power as the bike runs a total loss power system, this is now being changed to carry a Powerdynamo charging system to ensure sparks are there to do the job.
In spite of the dramas we were able to easily go past the Dry Lake Racers Australian club record of 126mph achieving 129mph on its first run and 131mph on its second run. This is impressive as the engine was babied along with no real effort to rev it due to the misfire”.
So what now Paul?
“We are planning to push Salt Bolt to exceed the top speed achieved by a Southern California Timing Association Moto Guzzi at Bonneville which was 171mph.”
I for one can’t wait to see the results. It’s a fantastic effort so far. In fact, as we started with credits it seems a mighty fine way to end. Salt Bolt is a credit you Paul Marcos, and you are a real credit to racing. Thanks for the feature on Rooneycyle.