I've been meaning to get my Guzzi on the dyno for a while to make sure the jettings about right.
Riding it around it felt fine at the top end but a little weak around 3k
It was originally fitted with 135 main jets but I'd swapped the exhausts out that it came with to a pair of Armour stainless. The bikes covered 42k and has the standard air box and engine internals.
So
off to the Dyno today. Thought I'd try a different dyno this time and I'm really pleased I did. its run by a couple of Brothers - proper old school mechanics who tune and build a few bikes for TT racers.
First task is to tie it all down. Next task was to drill a couple of holes through the baffles in my new exhaust system to get the sniffer in there.
Sam putting it through its paces
The Verdict
what do you thing a 1981 950cc Guzzi spada produces at the back wheel?
Well! The jets were too big for a start. Bikes tend to feel better on the road when they're too rich - mine felt great at the top end but only produced 39.5 BHP
We dropped the main jets down to 125 and ran it again - the mixture was much better and the bike produced 43.5 Bhp - Sams suggestion is that I need to go to 120 but unfortunately we didn't have any 120 jets to give it a go.
10 sizes on the main jet was worth 1.5 on the air/fuel ratio. The rpm plot was a waste of time, wasn't worth printing, the points were causing loads of spikes and anomalies at higher rpm so Ive ordered a dyna ignition to tame the sparks.
All in all a good couple of hours to get the bike bottomed out and moving in the right direction.
A couple of great guys who it transpired are ex Laverda riders and just happen to look after my old Jota that I sold years ago.
The work shop was full of racing Ducatis and Fireblades this morning. Worth the visit just to see those
If You are looking for a Dyno or conventional bike work in the East Midlands I can''t rate these guys highly enough - total cost to sort the Guzzi £50.
http://www.sprracing.co.uk/dyno?osCsid=0q7atnpt3dqtspilhck5j60p37