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Posted

Hello all!

 

I need to check the timing on my 2003 V11 Sport, but I don't know where to find the appropriate dial gauge support. Does anyone know where I might be able to find one? Also, can anyone recommend a good dial gauge, as well?

 

Thanks in advance!

 

--Ted

Posted

Since the timing is "fixed" , I don't know what you are going to do.

Posted

I had the same thought

Do you mean Valve timing?

Posted

I had the same thought

Do you mean Valve timing?

Under the "Check of the Timing System Setting" in the manual it says to "fit a dial gauge support into the LH cylinder's spark plug hole. Then fit the gauge into the latter."  This is to find TDC with valves closed. Then, one proceeds to turn the index plate attached to the crank to make sure the timing marks are aligned.

 

 ​I've attached a photo of the procedure. #5 is the dial gauge support, with a dial gauge resting in it.

Timing.jpg

Posted

I think you are looking at doing something that is not necessary unless it is running terrible , will not start or is backfiring upon start-up. 

 This is a check of the  camshaft  timing would be the proper term. 

Posted

I think you are looking at doing something that is not necessary unless it is running terrible , will not start or is backfiring upon start-up. 

 This is a check of the  camshaft  timing would be the proper term. 

I am rebuilding the engine from the bottom up.

Posted

No kiddin' ? 

You can catch a tool truck and get one or a machine shop tool vendor if you want a permanent one. If there are any European or British bike shops around you , you might be able to borrow the stuff over the weekend or they will help you do this.

  • Like 1
Posted

Under the "Check of the Timing System Setting" in the manual it says to "fit a dial gauge support into the LH cylinder's spark plug hole. Then fit the gauge into the latter." This is to find TDC with valves closed. Then, one proceeds to turn the index plate attached to the crank to make sure the timing marks are aligned.

You could make your own protractor and pointer, since if you are building your engine you have the skills. The crank sprocket is about 25 teeth, so your protractor only needs to be more accurate than 360/25 degrees for the crank, and 360/50 degrees for the cam. Your old high school protractor is more accurate than 7 degrees. You need to be sure that your camshaft is not a tooth out relative to the crank, or your engine will be VERY sad, especially if a piston touches a valve.

As for the dial gauge, you might consider a drinking straw poked down plug hole, and feel when the piston reaches the top. There is 2-3 degrees of crank rotation where the "lost motion" at TDC & BDC mean that the piston barely moves. This uncertainty is much less than one tooth of the sprocket, so you could try it.

Marty

  • Like 1
Posted

Hi,

 

the most accurate, and easiest, method to check the TDC mark is using a cylinder stopper and a degree wheel. You don't need a dial indicator for that purpose.

 

Fasten the degree wheel to the rotor and screw the stopper into the spark plug hole. Gently turn CW until the cylinder is stopped and note the degree. Turn CCW until stopped and note the degree. Add the 2 values and divide by 2, that's the TDC. I fabricated a stopper from a spark plug by drilling it through, cutting a thread into the hole and inserting a screw rounded off at the end. Take care not to interfere with the valves.

 

If you want to check the timing of the camshaft, you ideally use two indicators fastened so that you can measure valve lift while turning the camshaft with 0mm valve play set. Take measurements every 2° of crankshaft, note down the valve lifts and determine the point of intersection. That's the one where the two curves intersect in the next picture.

 

https://db.tt/UitlzOqp

 

The best value is intersection 3° (crankshaft) before TDC. If the measured value is off a new hole needs to be bored into the camshaft wheel.

 

Here's a picture of the setup.

 

https://db.tt/gAp4wpUC

 

Cheers

Meinolf

  • Like 2
Posted

Hi,

 

the most accurate, and easiest, method to check the TDC mark is using a cylinder stopper and a degree wheel. You don't need a dial indicator for that purpose.

 

Fasten the degree wheel to the rotor and screw the stopper into the spark plug hole. Gently turn CW until the cylinder is stopped and note the degree. Turn CCW until stopped and note the degree. Add the 2 values and divide by 2, that's the TDC. I fabricated a stopper from a spark plug by drilling it through, cutting a thread into the hole and inserting a screw rounded off at the end. Take care not to interfere with the valves.

 

If you want to check the timing of the camshaft, you ideally use two indicators fastened so that you can measure valve lift while turning the camshaft with 0mm valve play set. Take measurements every 2° of crankshaft, note down the valve lifts and determine the point of intersection. That's the one where the two curves intersect in the next picture.

 

https://db.tt/UitlzOqp

 

The best value is intersection 3° (crankshaft) before TDC. If the measured value is off a new hole needs to be bored into the camshaft wheel.

 

Here's a picture of the setup.

 

https://db.tt/gAp4wpUC

 

Cheers

Meinolf

 

Nice fixture on the cylinder head but overly complicated. A piece of scrap steel 6mm plate bolted to one of the valve cover bolt holes and a magnetic base/stand with a dial indicator attached to it will do the same thing for about $60. Yes the full stop method you outlined is the best way to find TDC.

Just about any cheap dial indicator and magnetic stand you can find on ebay will do. Set to zero valve lash with a feeler gauge and measure the valve timing at 1mm lift.

Ciao

  • Like 1
Posted

...If you want to check the timing of the camshaft, you ideally use two indicators fastened so that you can measure valve lift while turning the camshaft with 0mm valve play set.... If the measured value is off a new hole needs to be bored into the camshaft wheel...

This is new information to me. I thought that the only timing I had to get right involved the timing chain and sprockets. Have you found camshafts which have the dowel pin drilled in the wrong place, or are you modifying and optimising your engine?

Posted

Hi,

 

it's about blueprinting the engine. I have yet to see a Guzzi engine where the actual and indicated TDC are identical. Offsets are typically in the range of 1-2°, but I have also seen 4°. That might sound like a minor deviation, but setting the timing right is probably the cheapest and most noticeable tune-up available. And if you are doing it anyway then setting the camshaft wheel so that the lift of the exhaust valve and opening of the intake valve are coinciding at 3° before TDC is the recommended value. I remember that L.Apfelbeck even recommended values of up to 15° for engines with ram rods.

 

I wouldn't modify the dowel plug in the camshaft, but instead drill either a single hole at the necessary offset into the camshaft wheel or bore another 4 holes with 72° degrees offset. That would give you the option to offset the timing by +11.4/-7.6, +3.8/-15.2, +15.2/-3.8, +7.6/-11.4 degrees respectively.

 

On models with ECU (the picture in my previous post is a LM3) I would only correct the timing to factory specs or a slight advance. I don't know where in the ECU code the ignition and injection timing is calculated. Changing the value to more than the 3° before TDC  can be compensated for the ignition values by adding the value to the ignition tables, but I don't know where this can be done to the injection values.

 

Cheers

Meinolf

  • Like 1

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