7 replies to this topic

[miniGTS]

I set up the carbs as best I could by setting the jets 2.5mm down from the bridge. Both are as close as humanly possible, springs are new red springs and needles are GY. It's running way better than how I had it initially with spring mismatch and when I was trying to get the jet nuts turned out an equal amount of turns by counting... Surely I was doing that wrong...

Anyway, it seems to be running better now, revs up OK not great and starts quick and easy.

I don't know what cam is in there as it was done many years ago and stood for as many years before I got back into the project. I assume it's impossible to tell what cam is in there, even if it's removed... Though at this stage, that's not an option.

So the question, do it sound like a lumpy cam, poorly tuned carb, timing slightly off or just a terrible exhaust?

Oh, the Link https://photos.app.g...LFoAimTEuGadK69

Edited by miniGTS, 07 September 2024 - 09:04 AM.

[Spider]

Lumpy cam.

You can measure what cam you have there with the engine in easy enough.

[Lplus]

I set up the carbs as best I could by setting the jets 2.5mm down from the bridge. Both are as close as humanly possible, springs are new red springs and needles are GY. It's running way better than how I had it initially with spring mismatch and when I was trying to get the jet nuts turned out an equal amount of turns by counting... Surely I was doing that wrong...

Anyway, it seems to be running better now, revs up OK not great and starts quick and easy.

I don't know what cam is in there as it was done many years ago and stood for as many years before I got back into the project. I assume it's impossible to tell what cam is in there, even if it's removed... Though at this stage, that's not an option.

So the question, do it sound like a lumpy cam, poorly tuned carb, timing slightly off or just a terrible exhaust?

Oh, the Link https://photos.app.g...LFoAimTEuGadK69

 

Did you just leave the jets at 2.5mm down?  It is normal to adjust them each one flat at a time up or down to get the best mixture.  That sound could be rich mixture, but could also be the cam, so try adjusting the mixture first.

[miniGTS]

I just left it at 2.5mm down for now. I think it's a bit rich but also don't quite want to adjust the nut yet

[miniGTS]

Lumpy cam.

You can measure what cam you have there with the engine in easy enough.

How is it done?

[Spider]

How is it done?

 

Remove the radiator and fit a degree wheel up to the harmonic damper

 

 

You can clock it in to get TDC a few ways, however to work out what the grind it, just working off the Flywheel or Timing Cover markers will be fine. If you wanted to clock in the cam (to set it's timing in relation to the crank), you'd find TDC by using a piston stop.

Then remove the rocker cover, and set up a Dial Gauge, on a spring cap will be fine

 

 

Plugs out, then turn the engine over by using a socket and handle on the front Crank bolt.

 

This is a very accurate real world method of measuring it, as the engine is assembled and the valve train loaded by the valve springs.

 

[68+86auto]

From your other post now we know that you are running way too rich due to the fuel level being too high. This can have a few different causes which have already been listed in the other thread.

 

 

 

I had suspected this but didn't want to get involved.

[miniGTS]

Yes, seems I have a few things to check and sort out. Hopefully it'll run much better