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Hi

Has anyone other than pedro had any experience with the rubber intake manifolds (30.01.55) from NLM / Mdina? I need to order a pair and am wondering if pedro's problems were connected to the 501 engine positioning. The alternative seems to be Start Gomma (not much difference in price) but I would prefer to order from Mdina as long as the quality is OK.

Thanks in anticipation.

I bought a pair from Mdina in December and they appear to be very good. Fitting them really improved the running of my previously lumpy Sport.

Mike

Thanks Mike. Good to know. Dave.

Me again, I can tell you that the Start Gomma rubbers are in a different league as far as quality is concerned, much more substantial.

I had the same problems as Pedro with the manifolds for the 501 engine (never that much with 350) for years, they are tearing from the inside to the outside in the corner of the fold for the tube that is in the head. I was happy when they lasted for one season. Currently I´m very pleased with the ones I´ve put on Dulcinea, 19.000 km since may 2017 without problems. I guess they come from Alex/Italy (not 100% sure, because desperatly I tried diferent sources).

In Rocinate there is the original filterbox of the 350 supporting the carbs. Because Dulcinea wears Polini filters I supported the carbs with a strip of metal from one of the cover-screws of the carb to the frame. norbert

Thanks Pedro for the confirmation. I will order from Start Gomma (it's just that I had a bad experience shipping from Italy recently).

Thanks Norbert for the information. I believe my manifolds to be original and I have an original air filter box (so support should be OK). There is quite extensive cracking on the inside of the carburettor side although nothing on the outside, and I don't know they are leaking, but they are next in my process of elimination.

Dave

You may even get an e-Christmas card from them next year.

norbert wrote:Because Dulcinea wears Polini filters I supported the carbs with a strip of metal from one of the cover-screws of the carb to the frame.

k-DSCI0006.JPG

norbert

Using S&B pods I have big zip ties up to the frame taking the strain on both the 350/2C hybrids. I did try the Polini elbows for a while but they needed drastically leaner main jets to run at all well (with PHBH28s and L5 cam). If I get them set up properly I will rig yup a metal support as you have.

72degrees wrote:

norbert wrote:Because Dulcinea wears Polini filters I supported the carbs with a strip of metal from one of the cover-screws of the carb to the frame.

k-DSCI0006.JPG

norbert

Using S&B pods I have big zip ties up to the frame taking the strain on both the 350/2C hybrids. I did try the Polini elbows for a while but they needed drastically leaner main jets to run at all well (with PHBH28s and L5 cam). If I get them set up properly I will rig yup a metal support as you have.

Yes, I´m down to 120 main jets and still not convinced with the carburation (501 a little bit tuned, L5, PHBH28 and a artesanal escape/silencers without interferrence tube). Well as I said, I´m not really satisfied how the motor runs, but on the other hand it took me down and back to Spain and Italy, so I cannot complain that much either. The 501 R absolutely serie from a Camel that I have in Rocinante is (was) much faster and running better (more than 170km/h measured by gps, with 40l Harro tankbag and tent and sleeping back on the back). Last autumn I interchanged the carbs from one bike to the other and I´ve put the same parts inside that Rocinante had before. The result is that I now have two bikes that does not run really good

Hi All,
I have been following this thread with interest as I seem to be having great difficulty re-fitting a standard airbox. I bought a replica GRP unit from NLM many years ago with a set of rubber connectors, when I tried to fit them one of the rubbers split and the whole lot went in a box for another day. I am now refreshing my 1976 3 1/2 Strada and decided to dump the pod filters and weird jetting (didn't match any set-up I could find) and return to normality. I ordered a pair of connecting tubes from MDINA and on fitting the carbs and air box I hit a problem, the connecting tube on the LH/front carb appears to be too short or the wrong shape. The other possibility is that I have naffed it up somehow. I have looked at the manifolds on https://www.startgomma.com/en/moto-mori ... ifold-v521 and they appear to be different lengths, is that correct?
I have attached some photos of my current set-up for reference/ridicule as required. Any help will be appreciated.

Hi
With the original two piece manifold they will need to be rotated unscrewed to move the carburettor towards the centre of the bike this will reduce the required length of the elbow. It's quite a fiddle to get everything aligned but you need to do this before tightening the ring nut on the manifold.
Typically this means that the manifold does not bottom out in the head so it is secured by the ring nut.
The carbs should be vertical when viewed from behind.
Hope this helps
Mark

Cheers Mark,
That sounds like a good place to start.
Will adjusting the elbow length (I guess by screwing it in or out) alter the position of the vacuum gauge attachment point or do I need to dismantle the triangular flange as well to get the best alignment?
I'm sorry for all the questions, it just saves on the `Oh, now I see' moments.

You will only need to twist the inlet stubs a few degrees to alter the alignment. So start with them fully home and then back them out a little to get the angle right as Mark says. The carb will move up and across quite a way with a small movement of the inlet stubs.

S&Bs are poor compared to K&NS, proven less throughput on the flowbench when both were tested on the LEDAR set up.
One of my NLM inlets split disastrouly at Colombres rally 2 years ago, sidelining me midweek, and yes I tried all sorts to bodge it out there. The NLM carb to airbox rubbers were noticeably thin quality too. Startgomma parts are brilliant...

Hi All,
Thanks for the advice, it all makes perfect sense after the fact. Every thing is now aligned so I will stick with the MDINA rubbers for now and if they fail I will switch to Startgomma. It is great to find a supplier of quality Morini MDINA parts in Italy (it shouldn't be a surprise really) as now we are post BREXIT, MDINA postal charges are way out of my league; as with my last order, were 50% of the total cost, I will have to save up for a big order in future.
Hopefully I will have the re-build completed by the time Italy comes out of lock-down, which doesn't look like any time soon as the inoculation process is pitifully slow and a bureaucratic even on a good day.