It's official, Nova Transmissions are very very hopeless and not only that, given that they advertise close ratio gear boxes and dry clutches for the CB450, I think they might also be in breach of rules around advertising.....here's what we found and bear in mind through all of this that one gearbox and one dry clutch has cost me £2500 JUST TO BUY IT.
The gearbox fits fine in the crank cases (unlike the 750 gearbox which I had to modify to fit with different shims - That was £1500). However, when bolted up it wouldn't select 1,5 and 6 gears. This was eventually traced to the gear selector fork design - they fouled the inside of my standard CB450 crank cases so preventing gear selection. You try and select gear and the selector fork jammed against the top of the cases inside. The modification to get around the poor design was to shave grooves into the inside of the crankcases to get clearance. These are supposed to be drop in and go transmissions!
Next the dry clutch. Two problems here but related. Nova supply the dry clutch with a new primary drive gear. When the clutch crankcase cover they supply is bolted to the standard main cases on the CB450, the inside of the clutch cover grips their own primary drive gear and holds it solid - result, one locked up engine. It's like stacking glasses inside one another and jamming the top one in.
Nova's solution that they have in their own admission used on several CB450 customers is to supply a 1mm thick aluminum spacer to move the case out and prevent the gear fouling. This is fine until you install the clutch basket and it becomes 1mm closer in relative terms to the crankcase side cover. Result - the clutch basket rivets cut a deep groove in the cover - not good!
The solution was to take their primary drive gear and chamfer the edges to clear the inside of the clutch case casting. Result - everything turns fine with some small resitance. So, next job was to work out what was causing that resistance. Turns out the primary drive gear also fouls the standard oil dipstick so I have to either cut it off or get an aftermaket breather.
I questioned Nova about this yesterday. Their response was that the castings of the cover could vary and if the guy had a bad day casting them the tolerances couldn't be guaranteed. And this is my problem why!? Their caster is a subcontractor to them, not to me and it is their legal responsibility to ensure that what they supply to the end customer does what they advertise it does - plainly it doesn't.
They then let slip that since the original castings, of which mine may have been one, they now machine the covers and don't cast them....so clearly they were aware of the flaws in the results that the cast method produced but were still happy to sell them on at around £1000.
I asked for my cover to be replaced which they agreed to do BUT they want the cover back first and cannot guarantee when they will send another one out to me - in their words "it could be months". I just can;t risk missing another season - I've probably already got track rusty and so don't want to take this option.
So, finally my bike works and it will run when back in the frame for sure. That's cost me a further £250 to sort out and two days of travelling/petrol costs.
I haven't had a single product from Nova that has fitted without modification and I've recently found out a friend and very accomplished bike engineer has had exactly the same experience. How these people are allowed to trade these products when they are not fit for the purpose they are advertised for is beyond me.
My advice - save your money and put it elsewhere in the bike, Nova won't help you with the problems they send you and you're going to pay a lot for the privilege of solving their design shortfalls....
