street racing

The service in question addresses the now legendary Yamaha R1. This is not an umpteenth elaboration just for getting more horse power, but rather an expression of accurate and delicate made by those having more than 1000 readings on the test bench, alternated with an infinity of tests on the track. All data was gathered, observed and re-elaborated so as to define a recipe (tested on many models) capable of satisfying the most refined palates and capable of running on all surfaces, from city cobblestones to the vitreous asphalt of many European race tracks as well as the mountain passes of the Veneto, Trentino and Emilia regions.

The bikes
Two bikes are examined, one for the track and one for the road.

The engines
They are considered twins in as far as they are prepared by the same technician, Angelo Scarabello, using the same components and the same criteria. There are difference in the use of auxiliaries (radiators, flywheel etc.) but the base is the same and the results too.

The head is worked firstly having made a mould of the conducts, which is to allow for any defects to emerge and for a better planimetry correct vision of fluid dynamics. Upon a first analysis a careful observed with note how the conduct furthest to the left (no. 1) is bent and the flowmeter confirms its less efficient breathing compared to the other three. The justification of this choice by the constructors is probably commercial and tied to the fact that a carburetor battery was already made for the bike. The conducts are smoothed but not too much, as this would eliminate the micro vortex effect created on the walls (limit layer effect).

The compression ratio is revised (in the order of 13.8-14:1) by leveling the head, a very delicate operation, given the shape of the expansion chamber which easily wears the valve seats (especially the central ones). A silverware polishing will finish the job (a mirror gloss is used to eliminate as much as possible any carbon residue which generates undesirable anomalies in the combustion phase).

The exhaust conducts will have any parts jutting out from the valve guides re-profiled without being eliminated. The will also have a mirror finish.

The rest of the engine unit will see every component balanced and reassembled considering the fundamental smoothness and reliability (the pistons and connecting rods will be balanced with a tolerance of a tenth of a gram).

The only difference will be the presence of the battery recharge system for the road bike. The track bike will have none.

Much of the final result is to be attributed to the excellent study carried out by the same CEMES on the Air-Box which in time has changed shape and volume and the many air intakes to better guarantee airflow.

Running Gear and Suspension
The road bike will put on a good show with a front WP-ROMA fork.

With anodized tin stems and internal re-visitation, assured by a totally BREMBO brake system (mono-block pincers of SBK derivation). The same can be said for the posterior OHLINS; the rims, rigorously in magnesium alloy, provided by MARCHESINI.

The track bike with opt for entirely OHLINS front and back axles, hydraulics will be revised and to add a touch of extra class seeing the destination, a couple of extremely light MARVIC-PIUMA rims will appear, matched by a SPIGLER brake system (with 8 pistons), stuff to make your head spin!

We are not even going to dwell much on details such as fork plates (CAD designed) or the ergal and carbon fibre semi-handlebars. These details being almost too obvious.

Coming to weight, we have 175 Kg for the road bike and 167 Kg for the track animal, both with 10 litres of fuel in running order.

Only one affirmation, to the happy possessors who have found the excellent means on both city streets and in competition: "An animal the likes of my mother-in-law".

Click here to see photos and test the R1 at the test bench Borghi and Saveri

Components and final graphs

Air-Box Decomposed for Yamaha R1. Head engine of Yamaha R1 Superbike. They guarantee average + 5/7 hp