Only at HMB !
Models V7-Special, V7-750, V7-Sport, 750-S, 750-S3
We have developed a multistage performance kit that enables the 750 cc models to be driven in a manner appropriate to their needs !
Who doesn't know it, these engines are quite reluctant to rev, but need revs to get into gear. Plug and play solutions from the tried and tested Guzzi parts are not available off the shelf. The reason: the 750 cc models have a shorter crankshaft stroke than the 850/950 cc models. Later cylinders for more bore are ruled out because they are simply too long. We adapt these pistons and cylinders to fit the V7/V7-Sport engine block without further modifications.
The pushrods of the newer generation are also 4 mm too long for V7 models. In addition, the old pushrods (small ball at the bottom) are no longer available. These can be used with our kit, but they are quite heavy and mostly worn out.
You can also get the other stages of expansion to fit your engine.
The various measures we offer are ALL also available individually and make sense. Each individual step takes you a little further towards a contemporary engine. The points of displacement and camshaft alone bring a great deal, because that is where the main weak points of the series version lie. This short-stroke version of the 850 cc engine is far superior to the old 850 cc engines (T3, T5 etc.). With the large carburettors and further optimisations, it is well within the range of the 850 Le Mans models.
As always with us, we attach great importance to the suitability for everyday use and the longevity of the modifications. So "tuning" does not have to be seen as a negative word. Better materials and a healthy tuning of the measures guarantee this.
We stay close to the Moto Guzzi "construction kit", do not use exotic parts. This is important to guarantee the supply of spare parts later on. For example, gaskets and piston rings are standard parts of the later models.
The kits are staggered as follows:
Stage 1, Displacement:
Basis is a displacement kit with 88mm bore, nickasil cylinders and pistons from Gilardoni (2 pieces with rings and lightweight Pins and clips), reworked for the 70mm stroke crankshaft of the V7 models. This gives 851 cc. Compression is adjusted for the V7 combustion chamber, selectable between 9.5:1 and 9.8:1. The pistons are slightly lighter than those of the V7 Sport thanks to the lighter piston pins, so rebalancing of the crankshaft is unnecessary despite the larger bore. See stage 6.
Stage 2, Valve train:
4 Lightweight, matching short pushrods from our production, 4 matching push cups of the newer generation in original quality. This is not just about weight, but about moving mass. A high mass in the valve train always ensures increased wear and a lower rev limit.
Stage 3, Camshaft :
Here our proven valve train kit D-8.1 is used. Complete with valve springs and spring retainers. Due to the torque increase in the lower and middle speed range, this valve train kit including camshaft is ideal for this displacement class! We need an intact camshaft in advance.
In the case of V7-Special, we cannot offer an exchange camshaft. In this case, we would regrind your camshaft to the D-8.1 profile. This is possible, but is associated with a longer delivery time.
Stage 4, Carburettor PHF-36 with tapered intake manifolds:
PHF-36 carburettors with accelerator pump and matching intake manifold provide even more cylinder filling and power in the mid to upper rev range. Of course, you will receive the carburettors ready-tuned to your Guzzi. Because there are many misunderstandings and myths about carburettor tuning. The truth is, there is only one tuning that fits. Namely the right one for your engine constellation. To be fair, we have better measuring possibilities today than back in the 70s, and we use them.
Thread reductions for the M8 threads in the cylinder head are included, so there are no problems here either.
However, one has to accept a break with the original appearance. The nozzles are either straight or less angled than those of the old V7 models. Open Velocity stacks, clip-on filters or a modified airbox are then necessary.
Stage 5, Combustion chamber rework:
The icing on the cake. Here, the inaccuracies from the engine block, the crankshaft and the cylinder heads are adjusted. We start with a perfect sqishband, then the combustion chamber is gelled out. This guarantees exactly equal combustion chambers, which prevents vibrations. A correct squishband is very important for good combustion, brings torque and better exhaust values.
Stage 6, Crankshaft balancing:
Another icing on the cake. As already mentioned, the pistons of the displacement kit are not heavier despite the increase in bore. If you still want it to be perfect, or if you want to use our Pauter connecting rods, we offer balancing of the crankshaft. For this we need the crankshaft and the connecting rods. You will then get everything back perfectly balanced.
Stage 7, Pauter CroMo connecting rod set:
Extremely stable and light connecting rod set. This is not a must, but recommended at high rpm and for racing. As these connecting rods are much lighter than the originals, stage 6 (crankshaft balancing) must also be ordered.
Stage 8, test bench run:
If you decide to have your engine built up by us, the test bench run is an option. Everything is preset and tested here.