Mike Stewart Posted February 6, 2008 Share Posted February 6, 2008 I think we have a few things going on here, let me clear up some thoughts. The Guzzi's sold in the USA had tighter valve specs than those sold in the rest of the world. This was for noise pollution (loud valves save lives ). The USA valve lash spec was .05mm intake and .10mm exhaust. I know, how could any bike run with this lash? The problem we were having in the USA with running the tight specs was stalling when hot. I came across the fix by accident when I had read what Raceco suggested for the valve lash spec on the big block Guzzi. I tried the looser valve lash spec on my 2000 V11 Sport. The first thing I noticed after the valve lash adjustment was the idle speed was quite high (300+ rpm). I then noticed that I could idle down the motor to a smooth 1000 rpm. And yes the stall issue was cured. Was this from the valves running too hot or decreasing the duration of the cam by using looser specs, I am not sure. I then took the bike in for it's first service a few weeks later, the valves were readjusted to the USA spec and the bike stalled on me two times on the way home So David, if you are running the Euro valve lash spec. .10mm intake, .15mm exhaust, you idle speed may not change. I now use a valve lash between the Euro spec and Raceco's spec. on my bikes. Mike Sorry Dave, I must correct this! Tighter valves provide a higer idle, looser valves provide a more stable idle. If you lower the idle speed with the tighter valves to the same amount that occurs with the loose valves, the idle will get much more unstable. Link to comment Share on other sites More sharing options...
dlaing Posted February 6, 2008 Share Posted February 6, 2008 I think we have a few things going on here, let me clear up some thoughts. The Guzzi's sold in the USA had tighter valve specs than those sold in the rest of the world. This was for noise pollution (loud valves save lives ). The USA valve lash spec was .05mm intake and .10mm exhaust. I know, how could any bike run with this lash? The problem we were having in the USA with running the tight specs was stalling when hot. I came across the fix by accident when I had read what Raceco suggested for the valve lash spec on the big block Guzzi. I tried the looser valve lash spec on my 2000 V11 Sport. The first thing I noticed after the valve lash adjustment was the idle speed was quite high (300+ rpm). I then noticed that I could idle down the motor to a smooth 1000 rpm. And yes the stall issue was cured. Was this from the valves running too hot or decreasing the duration of the cam by using looser specs, I am not sure. I then took the bike in for it's first service a few weeks later, the valves were readjusted to the USA spec and the bike stalled on me two times on the way home So David, if you are running the Euro valve lash spec. .10mm intake, .15mm exhaust, you idle speed may not change. I now use a valve lash between the Euro spec and Raceco's spec. on my bikes. Mike I have never seen a published .05/.10mm US spec, so I think that is an urban legend. Possibly based on an earlier model Guzzi. My bike was previously set by my dealer to .10/.15, so when I read about the RaceCo spec years ago on this forum, I too made the compromise between .10/.15mm and .20/.25mm and went with the obvious .15/.20mm. This gave me a higher idle than the .10/.15. Your post years ago may have been what got me to try the more open clearance. Are you saying that once the tappets are open enough for a stable idle, there should be no significant change in idle at a higher tappet setting? Link to comment Share on other sites More sharing options...
ALdad Posted February 7, 2008 Author Share Posted February 7, 2008 When all else fails fallow directions. It works, what a concept! I started over this wknd. AND IT WORKED OUT PERFECTLY. Idle is fine. Runs with no hunts or pops . I think the closed TPS was off. So I now have learned to adj. the valves set tps and ballance. Gee I'm almost ready for some offical motoguzzi garage overalls. It's really cool that 30 people took the time to put in their opinions. Thanxs!! Alan By the way if any body has not done the swiss cheese cush drive mod ,DO IT noticeably smoother driveline. Link to comment Share on other sites More sharing options...
dlaing Posted February 7, 2008 Share Posted February 7, 2008 When all else fails fallow directions. It works, what a concept! I started over this wknd. AND IT WORKED OUT PERFECTLY. Idle is fine. Runs with no hunts or pops . I think the closed TPS was off. So I now have learned to adj. the valves set tps and ballance. Gee I'm almost ready for some offical motoguzzi garage overalls. It's really cool that 30 people took the time to put in their opinions. Thanxs!! Alan By the way if any body has not done the swiss cheese cush drive mod ,DO IT noticeably smoother driveline. Cool! We spent many hours writing the instructions. If you needed to run the idle TPS at that low voltage we'd have to spend another ten pages figuring out why! Skip the Official Guzzi Garage Overalls, buy some Red OshKosh and a patch or two, but then tell everyone that they are official Guzzi! (The money saved should be good for somethin ) Link to comment Share on other sites More sharing options...
motoguzznix Posted February 7, 2008 Share Posted February 7, 2008 Ernst, could you compare these values to those shown in the Cam thread: http://www.v11lemans.com/forums/index.php?...mp;#entry136976 I think those aftermarket cams are open even longer, but of course this depends on the given measurement clearance. What values show the original cams at 0.5 mm? Hubert Comparing the V11 cam with the Scola cams quoted at 0,5 mm lift you get the following figures: in ex V11 305 301 OOS 276 274 RS 307 306 KS 283 283 ROS 306 ? here are the OOS figures quoted the chart, supposedly an error. As you can see, the stock cam is one of the most opening cams, other companies make race cams with timing figures like this. For a street bike not favorable and the tuners get more power with shorter duration cams. The only disadvantage with the shorter cams is the higher valve accelerations contributing to more wear in the valve train. This is partly outweighed by the better lifetime of the exhaust valve with a shorter cam due to the better cooling. Shorter cams can also contribute to cleaner burning and thus less polluted exhaust gasses. But the V11 cam is very good compared to the cams used in the LM123T345 etc from the mid 70s on. This cam opened at 0,22 mm up to 390 - 400°. Exhaust valve failures were very common, especially when the lead was reduced in the fuel in the 80s. Link to comment Share on other sites More sharing options...
dlaing Posted February 7, 2008 Share Posted February 7, 2008 Here are some RaceCo numbers (all measured at .5mm) SS2 Raceco’s SS2 camshaft is an improved version of the SS (also known as the P3) camshaft. It has more lift, duration and overlap than the SS but retains the low rpm torque with extra power at the top end. It is accurately ground using state of the art equipment. The timing figures with a checking clearance of 0.5mm are as follows: Inlet opens 38 degrees BTDC Inlet closes 72 degrees ABDC Exhaust opens 72 degrees BBDC Exhaust closes 38 degrees ATDC Duration 290 degrees inlet and exhaust Cam lift 8.25mm Valve lift is 10mm approx. dependant on rocker ratio/geometry and production tolerances. Raceco SS3 camshaft The timing figures with a checking clearance of 0.5mm are as follows: Inlet opens 52 degrees BTDC Inlet closes 88 degrees ABDC Exhaust opens 87 degrees BBDC Exhaust closes 51 degrees ATDC Duration 320 degrees inlet Duration 318 degrees ehaust Valve lift is 11.32mm inlet and 10.97mm exhaust dependant on rocker ratio/geometry and production tolerances. SS4 Inlet opens 26 degrees BTDC Inlet closes 62 degrees ABDC Exhaust opens 51 degrees BBDC Exhaust closes 17 degrees ATDC Duration 268 degrees inlet Duration 248 degrees exhaust Valve lift is 9.6mm inlet and 9.54mm exhaust approx. dependant on rocker ratio/geometry and production tolerances. http://www.raceco.com/tech.html anyone know the numbers for a stock V11California/Jackal or a Quota? Link to comment Share on other sites More sharing options...
dlaing Posted February 7, 2008 Share Posted February 7, 2008 For comparison, from the manual the V11Sport is Inlet Opens 22° before TDC Inlet Closes 54° after BDC Exhaust Opens 52° before TDC Exhaust Closes 24° before TDC Duration 256° They don't specify what opening that was measured at, but it is quite a bit less duration than the 305 and 301 that MotoGuzznix posted. Link to comment Share on other sites More sharing options...
motoguzznix Posted February 8, 2008 Share Posted February 8, 2008 For comparison, from the manual the V11Sport is Inlet Opens 22° before TDC Inlet Closes 54° after BDC Exhaust Opens 52° before TDC Exhaust Closes 24° before TDC Duration 256° They don't specify what opening that was measured at, but it is quite a bit less duration than the 305 and 301 that MotoGuzznix posted. This is qouted at 1,5 mm measuring play. My own measurements confirm this: In/ex 254/253° at 1,5 mm Link to comment Share on other sites More sharing options...
luhbo Posted February 8, 2008 Share Posted February 8, 2008 Comparing the V11 cam with the Scola cams quoted at 0,5 mm lift you get the following figures: in ex V11 305 301 OOS 276 274 RS 307 306 KS 283 283 ROS 306 ? here are the OOS figures quoted the chart, supposedly an error. Einwandfrei, Ernst! Genau den Vergleich hab ich gesucht. Mit der OSS, der gestopften Quat-D und Doppelzündung müßte sie dann fast freiwillig aufs Hinterrad gehen, sollte man das brauchen , bzw, wie in meinem Fall eben nicht, überhaupt beherrschen Hubert Link to comment Share on other sites More sharing options...
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