I have just recommissioned a 750T that I bought at auction. The ride can only be described as a bone shaking, after half an hour your innards are well shaken up. The long front forks ( with 2 sets of castings for the front mudguard ) have been fitted with Bitubo inserts. So far I’ve just drained the fork oil , and 150ml of very black oil came out from each side. Does anyone know the correct amount of oil ? Or what grade for a softer ride ? I have seen other 750T with a completely different front end. Maybe the factory fitted what ever they had to hand ! Any advise would be very welcome !
The different front end might be more to do with a previous owner fitting a non-original front end after a ‘bump’, than the factory?
Ok. Thanks. It looks like I’ve put my post in the wrong category, but can’t work out how to change it. Sorry guys !
The ‘Fork Oil’ you removed is for lubrication only so has no effect on the ‘ride’. I can’t find a spec for the 750T but the 750 Strada, Targa etc use 100ml of oil. I usually use something like a 15 or 20 weight fork Oil.
So, the Damping is done by the Inserts. Are yours Air adjustable? They should be and have an air valve in the top. If so the psi is around 7-12 and you need a special pump!
Bitubo Inserts are quite good quality but have a tendency to seize up so make sure your compress easily but resist/damped as you extend them with no slack. Obviously remove the springs first!
As for the std springs. Rubbish! If you can find some ‘Progressive’ Fork springs it will make a significant improvement.
Good luck, Nik
Thanks Nik. My Bitubo inserts have no air valve and were previously sold by Gutsibits so I’ll ask them for any info. The bottom part of the forks are different from the Targa and Strada , in that they have 2 set of tapped castings for the front mudguard. I don’t know what other model shares them. But some 750Ts that I’ve seen have a different more normal front end. All a bit confusing !
That sounds like 850-T3 California. If I’m right then the bike has had a complete front end transplant because the T3 has 35mm forks and the 750T has 38mm forks. A photograph would be a great help.
DaiG, my bike has 38mm forks and I’m sure they’re original as even the new bike in the advert has them. The front mudguard has a metal bracket each side to raise it to take a larger front wheel , Gutsibits were not aware of this part as it does not appear in any of the part books, but luckily they had one on a secondhand mudguard as one was missing
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My 750T uses 38mm forks, which I believe are in common with the SP2, and T5 Series 3. They have an air balancing pipe between the fork tops, with a Schrader valve on the right hand one. The pipe was missing on mine but I managed to find a piece of suitable hard plastic pipe that fitted. Mine are loaded with 15psi, but the damping is very poor in any case. I’ve rebuilt the forks with new seals etc, and put 100cc of ATF in, as it’s only for lubrication (not damping). Springing is ok but could be a little stiffer or more progressive. Note that the dust seals tend to keep water in the top of the fork slider, so I took mine off and replaced them with Ariete gaiters, which do a much better job. I’ve had a reasonable go at getting new / updated dampers but Bitubo don’t make them any more.
Thanks BobNewBoy for the info. I presume that’s the set up my bike would’ve had when new . Good detective work about those other models, I’ve just looked at Google images of them and yes they do have the same front end , that is very useful to know. Is AFT a better lubricant than fork oil ? 100ml is what Gutsibits also recommended. I drained 150ml out of each side so that may have contributed to the solid ride , I did read about the front forks becoming “ pillars of Wood “ if the oil is overfilled ! Where are you based? As you are the first 750T owner that I have been in contact with.
I’m on the border between West Somerset and East Devon and usually attend the West Devon branch meetings / runs.
ATF is ok as a general non-foaming lubricant and many people use it in forks. A useful tip I’ve found is that Fowlers’ online parts list for Guzzi’s are very useful for cross-bike compatibility. There is a Guzzi parts list document numbered GU 31 92 00 20 I think I downloaded it from Gutsibits’ website. See
Yes, too much oil in the fork leg will lead to excessive pressurisation which could, in extreme circumstances, lead to a lack of fork travel. Also of course, too soft springs can see their movement used up quickly, also making the forks feel hard.
Again thanks BobNewBoy for the info. I’m in SW London but when I’m next down your way, I’ll definitely look you up as I would like to see your bike to compare various things.
Thanks for the parts link , this is the one that confused Gutsibits as the front mudguard heightening bracket is not shown !
Yes, that is a puzzle. If you need some perhaps Gutsibits would have a look through their collection of bikes they have, if you ask nicely? Otherwise it’s a part to make for yourself…..
I had to buy a secondhand front mudguard from Gutsibits, rob the brackets ( only needed 1 ) and then resell it , what quite a palaver !
Hello
I’ve moved this thread from the Big block to Small block section of the technical area of the forum.
Best wishes Chris
Thanks for doing that Chris , that was beyond my skills !