For Dellorto wizards.

two and half years ago, whilst in  Breganze an ILOC members Corsa suffered the eroded  float tips, it was sorted by Oro, the bike was hard to start and barely ran at all, creeping from Piazza Mazzini to Oro's in first gear only, the float tips had expanded and degraded, they were slimy and falling apart. Your theory (Piet) on the angle of the carbs is valid here, as immediately prior to this incident, I had the embarrassment of losing my footing when stopping, and me and my bike fell on the Corsa and knocked it to the ground, of course fuel ran out of the carbs, and on start up, it was rough, the valves (no doubt) having been seriously jarred and (probably) empty carbs as well
requiring more movement than normal.

three months later I found the same in a 1200, that came here for some help, balancing the carbs, as the bike was running erratically and reluctant to tick over, the owner did not have equipment to balance the carbs, but had rebuilt them himself about three months earlier, I took them off the bike to check inside and found all things to be in good order except the float tips the same as above Corsa.

Both bikes have been great ever since fitting the red tipped float valves and usage patterns have not changed.

The Khamsin is an extremely well maintained car and used hard regularly, on rare occasions by me, it is the property of a very well know celebrity chef who splits his time between London, France and Swiss, he has owned it for 30 years and it was totally restored twelve years ago, it started to be a problem about eight years ago, but continued to work OK, it got worse, it was mainly being kept and used in France through these years, it has now gone back to the original restorer in the UK, who diagnosed the problem after a bit of history questioning and without opening the bonnet, it was quickly repaired for not a lot of money and is now back to full power and working order.

There have been other Laverdas that I have seen and heard of, but not in recent times, with the same problem, eroded, slimey, breaking up float valve tips.

who wants to say what causes this?
CLEM
 
Where is the OBD port on the 3CL anyway? Carbs and electrics are an enduring mystery for most mechanics these days. I kind of see it as job security or at least safety in being regarded as a demigod!
 
wdietz186 said:
Where is the OBD port on the 3CL anyway? Carbs and electrics are an enduring mystery for most mechanics these days. I kind of see it as job security or at least safety in being regarded as a demigod!
Click to expand...

My wife is always very impressed.

Paul
 
Hi Guys
            From personal experience. My wife and I owned a couple of Aprilia Tuono twins for over ten years. Over the years I noticed the plastic fuel tanks "growing" in length to the point that the front mounting bolts wouldn't fit. Some creative eccentric bushes sorted that. However worse was to come when my tank dumped it's entire contents on the garage floor inches from a battery tender. When I removed the tank I found the fuel pump mounting face had badly warped, the pump was corroded and covered in gel like gunk and there was a fair amount of water in the bottom. These bikes were used mainly for European trips with around 18K on the clocks and extremely well maintained. New tanks are over two grand and none ever available used. So with nothing to lose I taped some coarse emery cloth to a flat plate and resurfaced the pump face. It took bloody hours, but I got there in the end. I'm fairly sure the ethanol content in Europe was higher than in the UK at the time and the bikes saw little use between trips which probably didn't help.
Ethanol is extremely hygroscopic and will cause problems in little used bikes. Best advice is to drain the lot and put it in the car. 
 
Best advice to avoid alcoholic issues with the bike, not to mention float valve tips, is to ride the damn thing a lot.

Otherwise, I'm quite sure that Aprilia is quite capable of buggering up a tank without ever puting any petrol into it.

Alcohol is stored in plastic containers, beer pumps and a lot of men.
Only the men develop problems because of it.

Paul
 
Gents,

Ref plastic fuel tanks.  Ducati will no longer change the internal fuel filters on most 10 year old bikes with plastic tanks as they can't always get the tanks to seal afterwards.  Plus they expand like the Denver and need modded mounts to fit.

Won't say it E5/10 related but....
Just saying.

Cheers
 
Laverda Atlas plastic fuel tanks (supplied by Acerbis) have had issues from the moment they appeared, no alc in the fuel at the time.  MZ1000 tanks expand to the extent the front mounting screws cannot be accessed.  Loads of other plastic tanks out there that are not affected... guess there are still people that do their homework. :D

piet
 
My 1981 Benelli 900 Sei has a plastic fuel tank. Never had any problems with it expanding it otherwise degrading. You have to be gentle with the fuel tap threads, but apart from that it seems indestructible. Not sure of the plastic type but it looks like HDPE.
 
Crap is crap.
No moaning about the good old days and resisting any sort of change because of an ultra conservative outlook will do anything about it.

My Gilera steel tank developped a hole under guarantee and years later, the paint was bubbling obviously because of fuel.
And that was on leaded fuel.

Paul
 
sfcpiet said:
Laverda Atlas plastic fuel tanks (supplied by Acerbis)  ..
Click to expand...

Think you've put your finger on the Bad Guys in all this, Piet  :o

Passing Laverda content:
On Zan? 750 fuel tanks (manufacturer, Acerbis), the filler cap swells up and seizes.  So now you can't get it off* -  or if you do, get it back on.  Great ...  >:D

Solution?  Get one off a Kawasaki (FFS, the Japanese could work it out. Go figure) .  Or do like I do and use the cap off an old Brembo master cylinder  :P

* Before finding the 'Brembo Solution', I used to carry a strap wrench with me, just so that I could fill the bike up ...  Now, how barking mad is that?  Thanks, Acerbis.
 
Well, the plastic tank on my '92 Husky TE is manufactured by Acerbis as well, never had any problems with it. plastic filler cap comes always off easily. Never using brute force to tighten it surely helps.
 
as always we have gone off topic, although still of great interest, what needs answering is.......
the question of ................what is causing the expansion, degradation, crumbling and sliminess of the original black tipped Dellorto float valve and is not affecting the red tipped ones, and has anyone experienced this?
CLEM
 
Maybe stick either type in a jar with your preferred soup of choice, local fuel you use and see what happens. What else touches them but fuel. The fuel used at the time the previous owner of my Pantah had it was the original Shell Optimax and I don't think it had Ethanol in it but it did melt the bottom of its Fiberglass tank off and I mean glued the carb slides up first and then the tank bottom fell off. It was fine for 10 years of fuel use before this happened. Fibreglass or plastic, there is something changed in the last 10 years eating fuel tanks and apparently needles and seats, and in a random way. Different fuel in different countries randomly acting badly on differant materials.
 
I talked to a fuel chemist in BP one time.
He said basically all C4 to C8 fractions from oil refinery crackers went into petrol.
Then there were additives and other chemicals.
Initially unleaded used Benzene to achieve the Octane rating.
After that was introduced the air quality in major UK cities had higher levels of Benzene in the air than the threshold limit value allowed for safe use.
Ethanol is seen as a quick fix by politicians to improve their green credentials as it is from a sustainable and renewable source.
The black tips vs red tips on the float valves is easy to answer, just a change of rubber formulation to resist attack from modern fuels. They will never tell us what they did to achieve this.
 
At one point a while back some dodgy independent petrol station operators where adding Tolurein to there underground tanks, there must have been a financial objective to do that. I forget the details but they got caught.
https://www.drive.com.au/motor-news/75m-fine-for-fuel-substitution-20100823-13i05
 
Ethanol also reduces dependency on foreign countries for petrol.
Any thing that can keep our kids from warmongering in places of no interest apart from petrol is a good thing.

Paul
 
The white carb floats for Dells definately swell causing them to stick badly on their shafts, though what causes it I have no idea. I recall Keith chucked them out and replaced with second hand black ones.
 
nick7 said:
The white carb floats for Dells definately swell causing them to stick badly on their shafts, though what causes it I have no idea. I recall Keith chucked them out and replaced with second hand black ones.
Click to expand...

Incorrect weight usually...

Just swapped out a set that had been fitted 20 years ago, no fuel-related damage to be seen.  Bike just refused to start decently due to wrong fuel level in the float bowl despite the float heights being set correctly.

Original black ones with correct weight are still available new.

piet
 
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