Author Topic: New Vintage Project, 250cc M-VG, Reconstruction of a 1933 French Jonghi 350  (Read 90737 times)

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Offline wobblywalrus

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Re: New Vintage Project, 250cc M-VG, Reconstruction of a 1933 French Jonghi 350
« Reply #120 on: December 24, 2018, 09:04:02 PM »
Merry Christmas to you,too, Patrick.  It is a nice time to stay in the shed and build things.  It is too dang cold outside. 

Offline Old Scrambler

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Re: New Vintage Project, 250cc M-VG, Reconstruction of a 1933 French Jonghi 350
« Reply #121 on: December 26, 2018, 12:12:04 AM »
Thank you for the good wishes.........and Merry Christmas :-)

Will you run synthetic oil in the crank?
2011 AMA Record - 250cc M-PG TRIUMPH Tiger Cub - 82.5 mph
2013 AMA Record - 250cc MPS-PG TRIUMPH Tiger Cub - 88.7 mph
2018 AMA Record - 750cc M-CG HONDA CB750 sohc - 136.6 mph
2018 AMA Record - 750cc MPS-CG HONDA CB750 sohc - 143.005 mph
2018 AMA Record - 750cc M-CF HONDA CB750 sohc - 139.85 mph
2018 AMA Record - 750cc MPS-CF HONDA CB750 sohc - 144.2025 mph

Chassis Builder / Tuner: Dave Murre

Offline thefrenchowl

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Re: New Vintage Project, 250cc M-VG, Reconstruction of a 1933 French Jonghi 350
« Reply #122 on: December 26, 2018, 10:51:38 AM »
Old Scrambler,

I will put very light oil in there.

The whole engine shares the same oil, contained underneath it in a biggish sump

(external oil tank is just a reserve, fed to the engine via a float like in a carburetor, will leave it on but will not use it)

The clutch is a wet brass/steel plates affair that needs even lighter oil to work proper.

I will blank all the oil communicating galleries and use separate ATP in the clutch and gear box compartments...

Patrick
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Offline rgdavid

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Re: New Vintage Project, 250cc M-VG, Reconstruction of a 1933 French Jonghi 350
« Reply #123 on: December 26, 2018, 01:02:05 PM »
For your clutch...ive got a husqvarna 390 automatic with brass centrifugal clutches, its recomended not to use atp but ohlins shock absorber oil, (there is a special husky auto oil but it costs a lot)  some differentials need a special oil aswell , like my iveco daily diff which has brass in it and some 50's and 60's peugots,  i think they recomend a "jl" oil ou something like that,  normal gearbox or diff oil wears the brass by holding the brass in the oil instead of letting it fall to the bottom of the casing,
I tried atp in my auto and can confirme this when changing oil.

Offline thefrenchowl

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Re: New Vintage Project, 250cc M-VG, Reconstruction of a 1933 French Jonghi 350
« Reply #124 on: December 26, 2018, 06:34:25 PM »
I have ran ATP in my Harley Bonneville KHK and also in most of my Harley Ks and Sportsters on the street over the years, these old things seem to like it... specially with wet clutches...

Patrick
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Offline thefrenchowl

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Re: New Vintage Project, 250cc M-VG, Reconstruction of a 1933 French Jonghi 350
« Reply #125 on: December 30, 2018, 07:17:50 AM »
Hi,

Started the tank extension yesterday... Since my alloy template wasn't quite symmetrical, I cut it in half:



Flattened and penciled it out recto/verso on a 0,8mm thick steel sheet:



Cutting it lasted a while...







Then big tube in the vice to get the approximate curves:







Back in the garage in 5minutes for more detailing!!!

See you,

Patrick
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Offline thefrenchowl

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Re: New Vintage Project, 250cc M-VG, Reconstruction of a 1933 French Jonghi 350
« Reply #126 on: January 05, 2019, 11:34:04 AM »
Bit more work done today,

Starting to look like summat....                                                                       











Patrick
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Offline thefrenchowl

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Re: New Vintage Project, 250cc M-VG, Reconstruction of a 1933 French Jonghi 350
« Reply #127 on: January 06, 2019, 12:40:00 PM »
Hi...

Fitted today the John Bull knee grips:





Then prepared all the parts needing mods for my machinist, I'll pop to see him next week...

Also ordered a few small bits to start sawing up the leather pouch that sits on the end of the gas tank...

See you,

Patrick
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...What exactly are we trying to do here?...

Offline ProjectROTM

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Re: New Vintage Project, 250cc M-VG, Reconstruction of a 1933 French Jonghi 350
« Reply #128 on: January 06, 2019, 02:08:43 PM »
Bit more work done today,

Starting to look like summat....                                                                       



Patrick

I like the seat position. I see what you mean about moving the seat on my bike even further back.

It looks like a great build so far.

Regards,

Project ROTM

Offline thefrenchowl

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Re: New Vintage Project, 250cc M-VG, Reconstruction of a 1933 French Jonghi 350
« Reply #129 on: January 09, 2019, 03:37:23 PM »
Hi,

68 today, a few prezzies and more stuff for the bike, including a ground bar to check crank vs cylinder deck parallelism...

I started 2 days ago to do the inserts that will go in the ball bearing locations so my machine man can clock the deck:





Inserted in locations:





Bolted up the timing cover to the crankcase, less than 1/2 thou clearance and nothing is biding, so I can be sure both locations are dead in line. So all ready for a trip to Crewe this Friday!



Also started the gas tap, high flow and a touch cumbersome, I'll revise it later to delete as many nuts as possible!





Bye for now,

Patrick
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Offline thefrenchowl

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Re: New Vintage Project, 250cc M-VG, Reconstruction of a 1933 French Jonghi 350
« Reply #130 on: January 11, 2019, 03:16:36 PM »
Hi,

Spent the morning in Crewe with my Fab Machinist...

Should have the bits back within 2 weeks

Afternoon spent modifying/shortening the tap...





The big single nut will be welded to the tank underside. It's big enough so I can pass a small filter through it...



Number plates in alloy sheet also arrived today:



As well as a smal sewing kit for the tank leather pad:



See you,

Patrick
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...What exactly are we trying to do here?...

Offline Old Scrambler

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Re: New Vintage Project, 250cc M-VG, Reconstruction of a 1933 French Jonghi 350
« Reply #131 on: January 11, 2019, 07:41:14 PM »
knit one; pearl two..............or is it more like shoe-laces? :-D

Great Project :-)
2011 AMA Record - 250cc M-PG TRIUMPH Tiger Cub - 82.5 mph
2013 AMA Record - 250cc MPS-PG TRIUMPH Tiger Cub - 88.7 mph
2018 AMA Record - 750cc M-CG HONDA CB750 sohc - 136.6 mph
2018 AMA Record - 750cc MPS-CG HONDA CB750 sohc - 143.005 mph
2018 AMA Record - 750cc M-CF HONDA CB750 sohc - 139.85 mph
2018 AMA Record - 750cc MPS-CF HONDA CB750 sohc - 144.2025 mph

Chassis Builder / Tuner: Dave Murre

Offline Koncretekid

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Re: New Vintage Project, 250cc M-VG, Reconstruction of a 1933 French Jonghi 350
« Reply #132 on: January 12, 2019, 10:44:24 AM »
I hope I get a chance to see you with this one!

Why the complicated twin outlet from the gas tank?  Why not just weld a 1/4" pipe thread bung, or coupler into the bottom of the tank and use a standard fuel tap?  Screen?  I usually end up cutting those off cause they are crushed or corroded.  If you're worried about silt or whatever, just let the coupling or bung pass thru the bottom of the tank so that any small amount of debris sinks to the bottom, unless the inside of the tank is rusty.  You can always put an inline filter between the tank and the carb.
Tom
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Life's uncertain - eat dessert first!

Offline thefrenchowl

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Re: New Vintage Project, 250cc M-VG, Reconstruction of a 1933 French Jonghi 350
« Reply #133 on: January 12, 2019, 11:49:35 AM »
Hi Koncrete Kid,

Thanks for your interest and queries.

Twin float chambers = twin outlets  :-D



The nut I'll weld for the tap will stick about 10mm higher than the bottom of the tank, still will fit a screen as well, I think the SCTA frowns on in line filters...

It's not a standard tap cause it'll have both a mechanical spring loaded lanyard from a twist grip and a magneto kill switch behind it.

Photos to follow soon, nearly finished it today...

Patrick

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Offline thefrenchowl

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Re: New Vintage Project, 250cc M-VG, Reconstruction of a 1933 French Jonghi 350
« Reply #134 on: January 12, 2019, 12:13:27 PM »
More work on the tap...

Cleaned all the nuts on the lathe to give them a more vintage look:



Made a plastic pulley to test the mechanical lanyard.

Driven by left hand side twit grip.





End of day, happy tests, I redo the pulley in aluminum:



1st spring a touch small, 2nd one a touch big... Will find a happy medium later!!!

So long,

Patrick
Flat Head Forever

...What exactly are we trying to do here?...