Bitubo Suspension

Anyone heard of these and would they fit?

There is a distributor in NZ, whereas there isn't a Matris distributor.

officine rossopuro used Bitubo on "ipothesys" and "zero".
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I see...

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in the UK they are mainly the purveyor of scooter replacement suspension

Guzzi used them for a while in the '90's. I was never impressed.

Maybe they are better these days?

Guzzi put them on the V7 "Racers" when they came out. I'm still trying to figure out why. I think it's because they were the cheapest shocks you could get with external reservoirs. They were horrid. Zero free sag resulted into getting launched on rebound.

Ok, sounds like my best bet is to get Pete to sort out a Matris setup and ship it all to NZ and i will get some help here to fit and calibrate,

Thanks for your comments.

I have put bespoke Matris on a couple of bikes. Even though they were the "right" springs for my weight, they were a bit too stiff. In talking with others on the subject, the general consensus was that you should lie about your weight. Claim you are lighter than you are. Maybe the people I ordered from were clueless. Pete may have some insight.

Peter Roper, PM sent

pokeyjoe wrote:

Guzzi put them on the V7 "Racers" when they came out.  I'm still trying to figure out why.  I think it's because they were the cheapest shocks you could get with external reservoirs.  They were horrid.  Zero free sag resulted into getting launched on rebound.  

That result is a lack of rebound dampening, not too stiff a spring.
Zero free sag (if rider sag is correct), indicates spring is too soft.

ghezzi wrote:

That result is a lack of rebound dampening, not too stiff a spring.
Zero free sag (if rider sag is correct), indicates spring is too soft.

Well, then, I'm confused as I can be. Free sag is just the weight of the bike on the suspension. If the springs ere too soft, I would think that the springs would compress under the weight of the bike. No?

I think it depends on pre-load (could well be wrong). Soft springs force you to crank up the pre-load to get to the correct 'total sag' and as a result the free sag reduces and is replaced by mainly rider sag......

ghezzi wrote:

pokeyjoe wrote:

Guzzi put them on the V7 "Racers" when they came out.  I'm still trying to figure out why.  I think it's because they were the cheapest shocks you could get with external reservoirs.  They were horrid.  Zero free sag resulted into getting launched on rebound.  

That result is a lack of rebound dampening, not too stiff a spring.
Zero free sag (if rider sag is correct), indicates spring is too soft.

Reading those made me curious, I looked up the V7 Racer's manual...
Its rear shocks have compresion and rebound adjustments, the manual gives some basic guidelines on how to adjust tmeh, it also has a "Causion" note, in bold capital, mentioning that if spring preload is increased, the rebound damping must be increased also.

So, looks to me that bitubos on V7 Racers, may be just fine - but not for a rider that do not know how to adjust them and have not even looked up for that in the owners manual.

It's been several years and my memory isn't what it once was (if it was ever any good). As I recall, the V7s have stiff rear springs to accommodate carrying a passenger (and avoiding litigation issues under those circumstances). I doubt if I had to increase pre-load. If anything, it was decreased. The rebound dampening was adjusted for comfort, but to avoid any bouncing. Even under those circumstances, there wasn't any free sag which always baffled me. Aftermarket shocks fixed everything.