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Does anyone have some clear instructions to setting cam timing when you have adjustable pulleys?
For example, if you need to set the timing to 104deg, how would you do it?

Thanks!
 

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Brad has a good talk about cam setup and centerline calculations here:

BikeBoy.org - Ducati Cam Timing - 2V models

I have some guidance on setting up TDC and some basic tooling:

http://www.ducati.ms/forums/40-spor...lve-clearance-cam-removal-degreeing-cams.html

Honestly, degreeing a cam using lobe centers is the same on a Ducati than anything else. If you have never degreed a cam, I'd brush up on how to read a degree wheel or get a buddy that has done it before. The biggest key is to make absolutely sure you get TDC right on the degree wheel. Use a piston stop to determine TDC.

Scott
 

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Brad has a good talk about cam setup and centerline calculations here:

BikeBoy.org - Ducati Cam Timing - 2V models

I have some guidance on setting up TDC and some basic tooling:

http://www.ducati.ms/forums/40-spor...lve-clearance-cam-removal-degreeing-cams.html

Honestly, degreeing a cam using lobe centers is the same on a Ducati than anything else. If you have never degreed a cam, I'd brush up on how to read a degree wheel or get a buddy that has done it before. The biggest key is to make absolutely sure you get TDC right on the degree wheel. Use a piston stop to determine TDC.

Scott
...and I would add - take your time, and measure everything two or three times to be sure that it is right.



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Just don't go past tdc with the piston stop in. Don't ask how I know.

Sent fra min SM-G930F via Tapatalk
 

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There are various types of tdc finders. It behooves one to use a type that will not result in damage. Poor technique can overcome the best of tools.
 
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if you do use a piston stop, rotate between tdc firing (both valves closed) and tdc overlap (exhaust valve opened and almost closing). between tdc overlap and tdc firing the inlet valve opens fully and can hit a stop, and may bend the valve.

so go past tdc firing, fit stop, go back and forward from there.

know and understand what you expect to be happening when. i used to see apprentices standing and looking at engines totally lost because they couldn't sketch a valve lift with crank rotation diagram. it really confuses people, so learn what and when first. then it's easy.

get a degree wheel that makes sense. i use an old crane one that goes the wrong way arrow wise for the ducati motors, but the numbers are all referenced to the events either side. i have a vee two one that goes from 0 to 360 and to me is really confusing and it totally doesn't relate to the numbers used for valve timing - which are all before and after tdc and bdc. you don't have any numbers over 90, and a wheel that reflects that makes sense to me.

the numbers you get probably won't match the spec. some people just can't handle that. i don't get why.
 

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When the numbers I get don’t match what I was supposed to get, my first assumption is that I’m not doing something right. Usually I find that is the correct assumption. Especially, as you note, if I’m using a degree wheel that doesn’t go both ways from TDC.
 

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I know there is a bunch of do it yourself people here but cam timing would be easiest learned with someone walking you through the process. I would find someone who has done it successfully more than once and have them teach you one on one. That way if you get stuck or have a question about something you can stop,ask and discuss what they are doing and why.

Like Brad said most of the time you do not get as advertised numbers so you need to be able to make sure that you are doing it correctly before assuming it is just the cam. Pay close attention to the quadrants and make sure you are reading the lift gauge correctly , I use both metric and inch indicators and have gotten crazy numbers more than once because I had the wrong gauge in the tool and was reading at the wrong lift.
 

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if you do use a piston stop, rotate between tdc firing (both valves closed) and tdc overlap (exhaust valve opened and almost closing). between tdc overlap and tdc firing the inlet valve opens fully and can hit a stop, and may bend the valve.

so go past tdc firing, fit stop, go back and forward from there.

know and understand what you expect to be happening when. i used to see apprentices standing and looking at engines totally lost because they couldn't sketch a valve lift with crank rotation diagram. it really confuses people, so learn what and when first. then it's easy.

get a degree wheel that makes sense. i use an old crane one that goes the wrong way arrow wise for the ducati motors, but the numbers are all referenced to the events either side. i have a vee two one that goes from 0 to 360 and to me is really confusing and it totally doesn't relate to the numbers used for valve timing - which are all before and after tdc and bdc. you don't have any numbers over 90, and a wheel that reflects that makes sense to me.

the numbers you get probably won't match the spec. some people just can't handle that. i don't get why.
That's a good point Brad on valve interference. I took the belt off so the valves were dead when I set TDC with the piston stop.
I agree with Brad and Ducvet; it can be confusing and not intuitive unless you can get your mind around 90 degree quadrants (BTDC, ATDC, BBDC, ABDC) and what the cam is doing.

Good luck.
Scott L.
 

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Just gonna say it.
If you don't have a solid feel for how motors work, and what is happening when, i.e. cam timing...
Don't attempt this without help from someone willing to assume your financial responsibility on said motor.
I'm not a rocket scientist, and don't think one is needed. But I do firmly believe that you need to understand what you are changing/measuring/optimizing.

If you do not understand the basics of cam timing, and what changing it does to an engine...
leave it to some who does.

Really!
 
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