Breva 750 gearbox

Hi hi I’m new to the club and forum. I’ve bought a 2006 Breva 750 with 20000 mile on the clock. I’ve only ridden it twice but I noticed when I try to select first gear, it seems to be trial and error whether it goes in or not. When I contacted the previous owner he said that these guzzi gear boxes are very agricultural and when the weather warms up it will get better! I can’t believe that when these bikes leave the factory they would have this problem. I’m in the process of changing all of the oils filters plugs etc and when I drained the gearbox oil it was like treacle! I’ve got a feeling someone has put bevel oil into the gearbox, I haven’t ridden the bike yet as I’m still working on it. Does anybody out there think that this could be the cause of my problem?

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Where are you based, mate?

Near Winchester Hampshire

I have owned mine from new, for 20 years, it was always a pig to slot into first when the engine is cold, in this sort of weather, later ones benefitted from a gearbox mod

however worth checking is that the clutch operating arm is free and lubricated, if its seized, then its a skilled job to remove it without breaking off the lugs ( I use a very good engineer to maintain mine)
also check the adjustment of the clutch cable, and the play on the pushrod
as well, use a spray white grease to lubricate the rose joints on the gear linkage, they get dry and can add to problems
I tend to get all my oils changed on every other service, because oil is cheaper than bearings

also worth checking, undo the drive shaft gaiter and check for water ingress, if its torn you need to replace it anyway
again a tip from my engineer, put a couple of tea spoonfuls of gear oil inside the gaiter/drive shaft, this will splash about and help prevent corrosion as its a dry unit, also check that the output shaft seal is ok on the gearbox, if the drive shaft gets any corrosion it tears the seal and oil leaks out, they can still fail with age or lack of use, as mine did after a long run across Europe, probably dried up through lack of use

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Thank you for your tips they are most welcome. I’ve got the clutch arm off for cleaning and greasing and same for the gear linkage. I’ve removed the clutch plunger to check for corrosion and will be replacing the rubber seal and spring that sits on the arm. I’m also fitting a new clutch cable as the old one is a bit snaggy.
You mentioned about a modification that was made to the gearbox, what was it?

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The gear problem will possibly be gone when you pour fresh, correct oil. But yes, disengagement of the clutch plays a big part in how smooth a gearchange happens. This is a side effect of dry clutch solution. So, do the oil change, have a ride; if nothing improves, do the clutch lever job. Once this failed, you’ll know for sure, this is Guzzi! A historic gearbox in a fresh-look wrapping:)
The mod our collegue mentioned could be the one where Guzzi decided to go down on neutral numbers from four to just one. Brevas 2004 already had it, no idea what year this was introduced though.

Thanks again for your help!!!

Somewhere I have the service manual and updates ref the gear box modification
about that time they also changed the dipstick
one important point, keep an eye on the engine oil level, there is not much in it and running it low will damaged the bottom end
mine used to drink a bit of oil at first, but as I rev the nuts out of it and ride it very hard often 2 up, it has settled in nicely
which bit of the planet are you on ?
I can always forward some techie stuff to you, and I think I have a spare manual someplace

That would be great! I think I was given a manual from the guy I bought the bike from. If it’s the same one, it’s A4 size with a red cover, the manual shows a breakdown of all the engine parts.
I live near Winchester.
I noticed that some breva owners have fitted a sump spacer, I don’t know if this is just for touring though

aha thats the one I have spare, I also have a full manual in PDF format, if I can work out how to find it ( technology is not my forte)
I am in Cheltenham so not far away
my technician is in Didcot if you need things doing
the high pressure fuel lines are due for replacement at that age, plus the two drain pipes from the petrol tank throat, one is to allow air in to prevent a vacuum forming, the other is tolet water drain out from the well
worth sticking an air line in and making sure they re not blocked
also while you are at it, change the fuel filter inside the tank
and grease the head bearings
one other point to check is the connector for the regulator
and keep the battery on an optimate or similar as the onboard mice drain the elektrikery y out oif of it after two weeks

This is to make the oil below the throw of the crank webs and so reduce the drag on the engine, but it also has the added advantage of placing the oil further out away from the engine into the cooling air.
I have a spacer on my Tonti bike that has a cast slot that pass right through around the crank throw to further aid oil cooling.

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Found this in my fuel tank, any guesses?

Yes its utter rubbish
that fat cockney bloke of wheeler dealers is always punting them for classic cars as a lead replacement substitute !!
modern Guzzis do not need lead replacement fuel
chuck it away
I wont use them in my classic car, because they dont work, something to do with low octane fuel supplied by the russians in WW2 causing the Merlin engines of the Hurricanes to run badly and eat valve seats, to be honest anyhting Russian is rubbish anyway ( My Uncle Sid did the Murmansk Convoys there and hated the place , tetra ethly lead was a 1920s invention to boost the octane rating of fuel and to prevent knocking ( pre ignnition)
Japan has never used lead in the fuel, so all japanese engines will run without it
most modern motorcycles will run without it

however, I have found that due to the government morons messing about with our fuel, modern fuels do not provide enough power, so I avoid E10 at all costs as it damages the fuel system and makes the bike run like a sack of bolts ( got caught out in Flanders once and I though I had wrecked the engine)
so only use E5 or the high octane stuff
and avoid supermarket fuel
i use either Shell or BP
my works vehicle is a very very high mileage ex police vehicle, always run on shell
emissions are perfect and economy is excellent

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I thought that maybe it was something to do with drugs.

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EER no
they carry those in a very different way

Ooo errr matron as Kenneth would say

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I was getting a bit worried! I thought any minute now I’ll have the police knocking on the door!:rofl:
I took your advise (thank goodness) to grease the head bearings, the seat on the lower bearing was damaged, causing it to not run smoothly, so ill be replacing both bearings.
Also the drain from the fuel tank was blocked with a creamy gunge, I’ve ordered up a new petrol filter, the internal pipes that connect to the pump seem fine.
Thanks again

Fork oil as well
and replace brake fluid
then ride it, lots and lots

Yeah, done the fork oil and brake fluid already, also changed brake pads as there wasn’t much bite to the brakes.
Is it advisable to change the fuel take gasket while im doing the filter?

Lead does not dissolve in petrol so what Rapheal said, load of hogwash :grin: