Camshaft data

[veloduke]

I have looked here but can't find any data for a Spanish 5. camshaft.

Does anyone have the data? I want to check the cam as my lower small bevel gear has two dots for timing.

I am sure to have chosen the wrong one....

[Jon Pegler]

What do you mean by a Spanish 5?
5-Speed? Widecase or narrowcase?
Engine number would help to be able to give you camshaft details.
Bear in mind that if you have two timing dots on the bottom bevel you usually time to the LH dot with a Spanish camshaft.
The keyway in a Spanish cam is in a different position to the keyway on an Italian cam, so mixing Spanish and Italian parts can lead to problems. It is always necessary to put a degree disc on the crank and check opening and closing events.

Jon

[veloduke]

Thanks Jon

OK, it's the camshaft itself that is marked '5.' (five dot).

It's from a narrow case Spanish 5 speed 250 Road engine no. MD 401570, possibly 1977.

Unfortunately I didn't take any photos of the cam itself.

I will check the timing, but I would still need to know what it is supposed to be.

[Jon Pegler]

The camshaft events for a n/c Road are as follows-
Inlet opens 55 BTDC
Inlet closes 90 ABDC
Exhaust opens 85 BBDC
Exhaust closes 55 ATDC

I would guess that your Road is 1976 rather than 1977.
I have a note of one about thirty engine numbers later than yours that was registered in Spain in 1976.

Jon

[veloduke]

The engine could well be 76, it's not original. The chassis is MD42142, and was reigistered in Barcelona on 28/3/1977, so I guess could also be a 76 depending on how long it was in the showroom.

I did some rough measuring of the cam timing, and it has longer opening duration than the cam data you gave;

Inlet opens 40 BTDC
Inlet closes 140 ABDC
Exhaust opens 70 BBDC
Exhaust closes 100 ATDC

Having drawn the timing figures on a circle, I can see that my cam is offset to the standard cam, so almost certainly needs correcting - looks like it's about 40 degrees offset.

I'll have to do a calculation to convert that to bevel teeth.

All part of the fun!

[veloduke]

A helpful Spanish chap has told me that the Road and 24H cams are the same, giving me cam timings that are the same as Jon's.

I think mine are different as I used incorrect clearances when determining the points of opening and closing giving the impression of longer duration, and have installed the cam a couple of teeth out.

Next job - correct the mistakes

[veloduke]

How it ended up, now running beautifully;

Present state 1 small version.jpg

I had used the left hand dot for timing.