Author Topic: Valve clearance adjustment questions  (Read 368 times)

Offline sstone14

  • New Egg
  • *
  • Posts: 44
Valve clearance adjustment questions
« on: May 26, 2022, 09:39:43 AM »
Is it possible to get the piston to TDC without a center stand or jack? I.e., can I get the bike in a higher gear by rocking the rear wheel on the ground, and then get the piston moving by rolling it gently and slowly? Or is this inadvisable?

Also, from what I can tell from youtube tutorials, you want the intake (rear) valve at its lowest point before you start moving the piston to TDC, and you get the intake valve there by rotating the rear wheel. But then you also get the piston to TDC by rotating the rear wheel as well? So wouldn't doing that change the position of the intake valve?

Just a little confused here.

Thanks, y'all.

edit: edited exhaust valve to intake valve. Had them confused.
« Last Edit: May 26, 2022, 10:02:05 AM by sstone14 »
'10 V7 Classic

Online Frenchfrog

  • Gosling
  • ***
  • Posts: 446
Re: Valve clearance adjustment questions
« Reply #1 on: May 26, 2022, 09:45:17 AM »
The only simple way is to jack the rear wheel , put the gearbox in gear and take the plugs out.Another way would be to take the alternator cover off and use the crank bolt to turn the engine in neutral after the plugs are out but it's more faff really.

Offline yogidozer

  • Gaggle Hero
  • *****
  • Posts: 2896
Re: Valve clearance adjustment questions
« Reply #2 on: May 26, 2022, 09:58:34 AM »
Centerstand, 5th gear, remove plugs, use a plastic straw to get piston TDC
check both valves to see if they are closed

Offline Kev m

  • Not your normal Hombre
  • Gaggle Hero
  • *****
  • Posts: 29894
  • Yo from Medford, NJ
Re: Valve clearance adjustment questions
« Reply #3 on: May 26, 2022, 10:04:41 AM »

No a jack or stand is NOT necessary. Yes it is possible.

It is even easier using a wheel roller:



https://www.amazon.com/Medduw-Motorcycle-Cleaning-Roller-Motorcycles/dp/B09GB51B3D/ref=asc_df_B09GB51B3D/?tag=hyprod-20&linkCode=df0&hvadid=563620908360&hvpos=&hvnetw=g&hvrand=1026323436439691996&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9003815&hvtargid=pla-1595565664688&th=1


Though personally on anything with a dry alternator I prefer to remove the alternator cover and turn the engine slowly and precisely using a wrench on the crank rotor nut.
Current Fleet

18 Guzzi V7III Carbon Dark
16 HD FLHP
13 Guzzi V7 Stone
11 Duc M696

Wildgoose Chase Moto Guzzi

Re: Valve clearance adjustment questions
« Reply #3 on: May 26, 2022, 10:04:41 AM »

Offline kidsmoke

  • Gaggle Hero
  • *****
  • *
  • *
  • *
  • *
  • *
  • Posts: 1229
  • It's never too late to be what you might have been
Re: Valve clearance adjustment questions
« Reply #4 on: May 26, 2022, 10:06:00 AM »
Having the rear wheel elevated and in gear is one option. I service my bike on my lift, front wheel in a chock, on it's rear wheel, so I use the other method, without having to lift the wheel.  Remove the plugs, pull the front alternator cover and turn the engine over by the crank. Remove the plug on the fly wheel and read the marks Mandello put there to find TDS. No harm doubling up using the chopstick method as well.

'78 G5
'85 LMIV
'93 1000S
'00 Jackal

Offline Kev m

  • Not your normal Hombre
  • Gaggle Hero
  • *****
  • Posts: 29894
  • Yo from Medford, NJ
Re: Valve clearance adjustment questions
« Reply #5 on: May 26, 2022, 10:18:14 AM »
Having the rear wheel elevated and in gear is one option. I service my bike on my lift, front wheel in a chock, on it's rear wheel, so I use the other method, without having to lift the wheel.  Remove the plugs, pull the front alternator cover and turn the engine over by the crank. Remove the plug on the fly wheel and read the marks Mandello put there to find TDS. No harm doubling up using the chopstick method as well.



His smallblock looks a little different, but that's the right idea.

I'm also think he might not have timing marks on the flywheel, but I'm not positive. I know I don't on my later 13, but his 10, not completely sure.

My CARC big block was really convenient, there was a plug in the center of the alternator cover for access with a socket. I didn't even have to remove the cover.
Current Fleet

18 Guzzi V7III Carbon Dark
16 HD FLHP
13 Guzzi V7 Stone
11 Duc M696

Offline John Croucher

  • Gosling
  • ***
  • Posts: 492
Re: Valve clearance adjustment questions
« Reply #6 on: May 26, 2022, 10:19:04 AM »
Having the rear wheel elevated and in gear is one option. I service my bike on my lift, front wheel in a chock, on it's rear wheel, so I use the other method, without having to lift the wheel.  Remove the plugs, pull the front alternator cover and turn the engine over by the crank. Remove the plug on the fly wheel and read the marks Mandello put there to find TDS. No harm doubling up using the chopstick method as well.



Put the transmission in neutral while doing this procedure.

Make a couple of marks on the Stator and Rotor that align at top dead center.  Then You will not have to look at the fly wheel hole.  A few degrees either side of tdc will not make a difference on the valve lift.  Being spot on is not critical.

Offline Caffeineo

  • Guzzi B00b
  • Gaggle Mentor
  • ****
  • *
  • *
  • *
  • *
  • *
  • Posts: 886
  • Location: Nampa, Idaho
Re: Valve clearance adjustment questions
« Reply #7 on: May 26, 2022, 10:39:31 AM »
Just did my V85. Bike in second gear on side stand. Both spark plugs removed. Use a thumb or finger to cover spark plug hole. Gently move bike forward little by little until you feel pressure on your finger. This is the compression stroke. Then put a plastic straw or similar in the spark plug hole and slowly repeat rocking the bike forward and feel the straw come up. You will get to a point quickly that you feel the engine turn and the straw does not move. This is close to TDC. Check the valves. Hope this helps.
2022 Moto Guzzi V85
2021 Beta Evo 250 Factory
2014 Husaberg FE501

Offline sstone14

  • New Egg
  • *
  • Posts: 44
Re: Valve clearance adjustment questions
« Reply #8 on: May 26, 2022, 10:45:02 AM »
Just did my V85. Bike in second gear on side stand. Both spark plugs removed. Use a thumb or finger to cover spark plug hole. Gently move bike forward little by little until you feel pressure on your finger. This is the compression stroke. Then put a plastic straw or similar in the spark plug hole and slowly repeat rocking the bike forward and feel the straw come up. You will get to a point quickly that you feel the engine turn and the straw does not move. This is close to TDC. Check the valves. Hope this helps.

Hi. Thank you, this does help a lot. But what about making sure the intake valve is at its lowest point before adjusting the position of the piston? The videos I've seen indicate that this is important. But it seems that the rear wheel rotation you have to do to adjust the piston to TDC would also change the position of the intake valve. Or is that just obvious, and the valves are supposed open and close as you move the piston to TDC?
« Last Edit: May 26, 2022, 10:49:14 AM by sstone14 »
'10 V7 Classic

Offline Kev m

  • Not your normal Hombre
  • Gaggle Hero
  • *****
  • Posts: 29894
  • Yo from Medford, NJ
Re: Valve clearance adjustment questions
« Reply #9 on: May 26, 2022, 11:11:36 AM »
Hi. Thank you, this does help a lot. But what about making sure the intake valve is at its lowest point before adjusting the position of the piston? The videos I've seen indicate that this is important. But it seems that the rear wheel rotation you have to do to adjust the piston to TDC would also change the position of the intake valve. Or is that just obvious, and the valves are supposed open and close as you move the piston to TDC?

For newbies I also think it is best that they watch the intake and exhaust valves open and close a rotation or two to figure out if the piston is at TDC of the Exhaust or Compression strokes.

Forgive me, I'm going into work mode and assuming nothing on your part.

Remember a 4-stroke engine works with 4 different phases of piston movement with regards to the valve train (camshaft movement).

The crankshaft moves TWO full revolutions for every ONE revolution of the Cam.

That means Piston DOWN, piston UP, Piston DOWN, Piston UP for one cycle of the valve train.

The phases are (and this is circular so it doesn't really matter where we start):

* Power Stroke (piston down, burning fuel, making power)
* Exhaust Stroke (exhaust valve opens, piston moves up pushing out expired gasses)
* Intake Stroke (intake valve opens, piston moves down drawing in fresh gasses)
* Compression Stroke (piston up, compresses gasses)

Cycle repeats.

This means when you're rotating the crankshaft (via tire or rotor nut) you watch. If the valve at the front of the head (closest to the exhaust pipe, I.E. the Exhaust Valve) opens and the piston is coming UP you're on the EXHAUST STROKE you'll need to go around again.

The Exhaust valve will close and the Intake (the one at the back of the head, closest to the throttle body) will open as you go around. You're on the Intake stroke now.

As the Intake Valve closes the piston will be heading up again on the COMPRESSION stroke. This is it.

When the piston gets to the top of the travel you'll be a TDC (Top Dead Center) of the COMPRESSION stroke.

This is the point where most motors (including all Guzzis I've ever worked on) have their lifters on the base of the camshaft lobes. This the point of most lash/play.

This is the point you check both the valves on THAT cylinder.

Repeat for other cylinder.

Bob's your uncle.

Back to writing a new Kymco OEM manual for me....
Current Fleet

18 Guzzi V7III Carbon Dark
16 HD FLHP
13 Guzzi V7 Stone
11 Duc M696

Online Anomaly

  • Hatchling
  • **
  • *
  • Posts: 156
  • Location: Southern Tuscany (mostly), Rhode Island (sometimes)
Re: Valve clearance adjustment questions
« Reply #10 on: May 26, 2022, 11:22:17 AM »
Though personally on anything with a dry alternator I prefer to remove the alternator cover and turn the engine slowly and precisely using a wrench on the crank rotor nut.

This-- if, as noted, you have the dry alternator
2012 v7 Classic, 1983 Piaggio Apecar P2
Sold: 98 BMW F650

Online Kiwi_Roy

  • Gaggle Hero
  • *****
  • Posts: 9591
  • Location: New Westminster BC
Re: Valve clearance adjustment questions
« Reply #11 on: May 26, 2022, 11:32:49 AM »
Is it possible to get the piston to TDC without a center stand or jack? I.e., can I get the bike in a higher gear by rocking the rear wheel on the ground, and then get the piston moving by rolling it gently and slowly? Or is this inadvisable? Thats a method I use sometimes, I sit astride the bike in top gear

Also, from what I can tell from youtube tutorials, you want the intake (rear) valve at its lowest point before you start moving the piston to TDC, and you get the intake valve there by rotating the rear wheel. But then you also get the piston to TDC by rotating the rear wheel as well? So wouldn't doing that change the position of the intake valve No just take it back 1/2" or so then approach TDC again


Just a little confused here.

Thanks, y'all.

edit: edited exhaust valve to intake valve. Had them confused.
Its not that critical you have it exactly TDC but its easy enough to do so why not get it as close as possible, You should be doing the valves with the bike stone cold.
I assume you are doing a V7II, does that have a dry alternator, I know the V7III is in oil.
On the exhaust stroke the valves rock at TDC, Exhaust is closing as inlet is opening, at TDC they are both open about the same.
Is it the first service by any chance?
Please confirm your model No
Good Luck
« Last Edit: May 26, 2022, 11:42:22 AM by Kiwi_Roy »
72 Eldorado
17 V7iii Special
76 Convert
Half a V9 Roamer

Moto Guzzi - making electricians out of riders since March 15 1921

Offline jcctx

  • Gaggle Hero
  • *****
  • Posts: 1412
  • Location: Cedar Creek Lake, Henderson Cty., TX
Re: Valve clearance adjustment questions
« Reply #12 on: May 26, 2022, 11:42:42 AM »
Now I realize why I love two stroke singles :evil: :azn: :azn:

Offline Cam3512

  • Gaggle Hero
  • *****
  • *
  • Posts: 6352
Re: Valve clearance adjustment questions
« Reply #13 on: May 26, 2022, 12:38:45 PM »
His smallblock looks a little different, but that's the right idea.

I'm also think he might not have timing marks on the flywheel, but I'm not positive. I know I don't on my later 13, but his 10, not completely sure.

My CARC big block was really convenient, there was a plug in the center of the alternator cover for access with a socket. I didn't even have to remove the cover.

You can drill/cut a hole in the plastic alternator cover, then add your own rubber plug.  When I had my V7 I acquired an extra cover to do just that.  You’re welcome to it if you want it?
Cam - NJ Rep MGNOC
'67 Stornello Scrambler
'71 Ambo Police
'74 V7 Sport
‘20 V85TT

http://mgnocnj.forumotion.com

Offline John Croucher

  • Gosling
  • ***
  • Posts: 492
Re: Valve clearance adjustment questions
« Reply #14 on: May 26, 2022, 12:43:16 PM »
Kev, this is on my truck.  Don't ask, we will have to get a political thread going, and the never goes good.





how to change your pc screen resolution

Offline LowRyter

  • Gaggle Hero
  • *****
  • *
  • *
  • *
  • *
  • Posts: 16139
  • Location: Edmond OK
Re: Valve clearance adjustment questions
« Reply #15 on: May 26, 2022, 01:11:15 PM »
Having the rear wheel elevated and in gear is one option. I service my bike on my lift, front wheel in a chock, on it's rear wheel, so I use the other method, without having to lift the wheel.  Remove the plugs, pull the front alternator cover and turn the engine over by the crank. Remove the plug on the fly wheel and read the marks Mandello put there to find TDS. No harm doubling up using the chopstick method as well.



this.

Another hint is to mark the rotor fin when it's at TDC.  That way you'll never have to use a chopstick or look for the timing marks with a flashlight ever again.  I have the Dis-side at midnight (right side) and S'not dis-side at 3:00 pm (left side). 
« Last Edit: May 26, 2022, 01:12:51 PM by LowRyter »
John L 
When life gets you down remember it's one down and the rest are up.  (1-N-23456)

Offline Kev m

  • Not your normal Hombre
  • Gaggle Hero
  • *****
  • Posts: 29894
  • Yo from Medford, NJ
Re: Valve clearance adjustment questions
« Reply #16 on: May 26, 2022, 02:49:33 PM »
This-- if, as noted, you have the dry alternator

He does - it's a 2010 V7C


You can drill/cut a hole in the plastic alternator cover, then add your own rubber plug.  When I had my V7 I acquired an extra cover to do just that.  You’re welcome to it if you want it?

Sure, I'll take it.

Kev, this is on my truck.  Don't ask, we will have to get a political thread going, and the never goes good.




how to change your pc screen resolution


 :laugh:   :thumb:  :boozing:
Current Fleet

18 Guzzi V7III Carbon Dark
16 HD FLHP
13 Guzzi V7 Stone
11 Duc M696

 

20 Ounce Stainless Steel Double Insulated Tumbler with donation credit
Buy a quality tumbler and support the forum at the same time!
Better than a YETI! BPA and Lead free.
Advertise Here