in my motocross bike and trial bike i use Motul offroad chain lube, it's the only chain lube that do not attract dirt, sure WD40 attract less dirt but the lube ?
There isn't a crank end float measurement published anywhere, and there are no shims on the crank (the only 'shim' is a spacer about 0.5mm thick behind the LH bearing on the output shaft in the gearbox). If you pull the RH case down using the case screws then obviously all of the clearance in the bearings is taken up with the inner races being pushed outwards, to counteract this I use a spacer under the flywheel nut to ease the RH inner race inwards and centralise the crank in the bearings by feel.
The crank bearings are per the parts list - 6305 C3 and 6304 C3 (the C3 clearance spec is important), I usually use branded bearings like SKF, Koyo or similar as they don't cost much more in real terms than 'budget' parts. Not sure where you are in the world but I am in the UK and use the Simply Bearings website for all bearings, seals, o rings etc.
but on the ignition side, original is NU305ECP not 6305C3
RAL 3020 Red is the nearest shade of powder coat you will get. The original Fantic red was a touch darker, so you would have to colour match something original with a vehicle mixing system colour chip at your local vehicle paint factors. Powder coating harder wearing than paint, but difficult to match with original colours.
Its a great STORY but running at 80:1 in an aircooled engine in Italy where it is probably warmer than it is in the UK......just not possible...... your engines are definitely ruined,I should have another look and rebuild them then use a bucket full of oil to a cup full of petrol.
i have some trouble to translate (sorry) but i understand that you think it's not possible to run at 80:1 ?
i ride my Fantic trial from years only in classic competition and trial practice, usually 10 liters gasoline 100 octane with 140 cc of sinthetic oil but last year i cheked ours engine and discovered inside a lot of deposit on pistons and head, and watching the bearing, pistons and cylinders they were full covered of oil (like a four stroke) so i decided (after suggest of my mechanic) to reduce the oil at 80:1 (our Beta evo run at 90:1)
consider that ossa and vertigo run at 120:1 and they run well, Beta enduro 250/300 2t self mix run from 0.8% to 1.6%
this is what really happen here in Italy in my garage and see with my eyes, and yes here is very hot ... but i never ride my bike on street and at high rpm
I was thinking stick with mineral oil.... is castrol 2t a good one or is there a more superior mineral based to use?.
40 years ago Fantic recommended run with mineral oil at 2% (50:1)
now i race the 240 and 300 at 1.2% (80:1) with synt oil (Motul 800-710 or other brand ) without any unusual wear, i tell you this because i have demounted my engine last year and the interior of the engine was perfect, so i think it's not necessary run at high percentage
i tried Oko, and it's much better than phbl 25, but now (due to the italian new rule in classic trial) i tried a PHBH 26 (from a 241) and i think works great
Hi Guys, Fantic reed valve pistons, both 245 and 305 can come with different configurations for the piston inlet ports, the middle port is a puffer port, directly opposite the exhaust port, doesn't really matter (in my opinion) wether piston has or hasn't got this hole, or can be machined if you really think it's necessary. In my experience, some pistons have no holes whatsoever, but can quite easily drilled/ machined to original spec.
So i can fit the Section piston in my 305 without problem ?
I've used a chap called Ellis Moore for one off gear cutting, great quality and the right price. He can copy old and worn bits and make new from the pattern of the old.
Moore Performance Engineering in London, do you think they can do a copy of the clutch basket at the right price ?
chain lube - sandy conditions
in General Trials Talk
Posted
in my motocross bike and trial bike i use Motul offroad chain lube, it's the only chain lube that do not attract dirt, sure WD40 attract less dirt but the lube ?