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Flywheel makings - help !!

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Perks View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Perks Quote  Post ReplyReply Direct Link To This Post Topic: Flywheel makings - help !!
    Posted: 03 Jul 2020 at 11:40
Hi all,

Can anyone help me with this one ?

I've a 1979 Spada which has an unknown history. I got it as a non or very rough runner - completely rebuilt the carbs (new jets and slides etc), had a rebore and new pistons and then set it all up as well as I could. The makings on the flywheel are simply S & D and were set where the pistons are at the bottom of the stroke. 

I'm having to assume that at some point the flywheel has been removed and re-attached 180 degrees out of sync. I ended up setting the timing with a piston stop and a degree wheel on the alternator bolt and then remarking the teeth on the wheel with paint at TDC, static and full advance for both pistons.

I've got the bike running reasonably well, but it won't tick over without choke. Having said that, it's still not run in on the new pistons yet, so maybe it will settle after a few miles.

My question after all that is: is it actually possible to put the flywheel back on 180 degrees out and would this in any way stop the bike running properly ? I don't really want to pull the engine and have 
to take it all apart.

I can't see why it would affect the running, but I've never fully stripped and rebuilt a Guzzi engine (yet !!!!) so don't know if it's crucial

Thanks for any help..... 
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Ken-Guzzibear View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Ken-Guzzibear Quote  Post ReplyReply Direct Link To This Post Posted: 03 Jul 2020 at 12:40
Yes it is very easy to put flywheel on in just about any configuration, there are marks to line it all up but if someone put it back wrong then the marks will not be in the correct place..... however it is easy to set up and mark it .... get engine TDC  do the D first =Right ... = Denso  then same with S=left=sinistro ...easy s is starter side ..... once you have TDC it is a simple matter to noch the flywheel each tooth is 3.75 degrees you can get it running just by that ...a timing disc is more accurate but Guzzi timing is quite forgiving I once set a RiTa system by eye then once engine running moved the distributor to where it sounded right on checking with strobe it was almost spot the info on the website for setting up Rita is real good to start with www.eurospares.com/elec.htm scroll down ...look in the manual for the timing for your bike same flywheel on T3 and V1000  but possibly different timing marks
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Perks View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Perks Quote  Post ReplyReply Direct Link To This Post Posted: 03 Jul 2020 at 19:09
Hi Ken,

Thanks for the quick reply and info. Sounds pretty much like what I've done and managed to get it running.

It does seem to run hotter on the right hand cylinder - hence that and the inability to get it to idle, was making me want to check the timing properly.

I did mark the flywheel with paint and counted 1 tooth from TDC for static and however many more for full advance.

I was going to try a sliding and graduated piston stop and a light bulb across the points to see if they were both operating the points at the same position for each piston. I was going to stick it in 4th gear and wind the rear wheel forwards to hopefully take up any backlash and see if my painted on marks were half accurate.

I've tried a strobe light in the viewing hole but the marks were so blurred I couldn't make out whether they were right or wrong !!

Cheers,

Perks
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Mike H View Drop Down
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Mike H Quote  Post ReplyReply Direct Link To This Post Posted: 03 Jul 2020 at 19:24
I always used an Allen key in the alternator bolt to turn it by hand, clockwise only of course (or it unscrews, but not always), plugs out of course. There is a large amount of slack in the drive to the distributor so I never had much luck with a strobe either. Wanders about all over the place.

If memory serves static timing for the Spada was 2° BTDC, which was a faint line just to the side of the 'D' or 'S'. That would make it above the letter in the timing inspection hole. You are turning it the right way for advance aren't you? One reason it may not idle is it's too retarded.

Also carb mixture screws and throttle stops need to be right. But also, even if set up right, it wouldn't idle on the throttle stops until it's been ridden a few miles and got properly warmed up. It's then you find out that you've set the throttle stops a bit too high so it idles too fast.




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Post Options Post Options   Thanks (0) Thanks(0)   Quote Normskii Quote  Post ReplyReply Direct Link To This Post Posted: 03 Jul 2020 at 19:57
After fitting new head gaskets they settle very quickly this tightens the valve clearances and can lead to poor low running. It’s worth re torqueing the heads and checking the clearances after the first couple of heat cycles. (And again after say 200 miles)
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Perks Quote  Post ReplyReply Direct Link To This Post Posted: 03 Jul 2020 at 20:26
Hi Ken,

Thanks for the reply - all good stuff and every little helps !!

Do you know if running hot is caused by the timing being too advanced or too retarded ?

I've not re-set the timing since I originally set it with the degree wheel on the alternator bolt.

There are no other marks at all on the flywheel other than the D&S - I've checked carefully!! Yes, marks very burred with a strobe. Practically useless !! 

I've tried adjusting the carbs. Spent a lot of time checking float levels, every jet has been replaced, checked for air leaks, set up the slides with a drill from the back side. Both bottom out together and they aren't suspended on the throttle cables. I've adjusted the mixture screws and the throttle stop screws, but it doesn't seem to make a lot of difference.

That's why I'm coming back to the timing. The RHS pot runs a lot hotter than the LHS - you can feel it just by holding your hand over it !

Running out of ideas and enthusiasm and summer's here !!

Cheers,

Perks
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Perks Quote  Post ReplyReply Direct Link To This Post Posted: 03 Jul 2020 at 20:27
Thanks Normskii,

Will give that a try - certainly can't do any harm.

All the best,

Perks
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Perks Quote  Post ReplyReply Direct Link To This Post Posted: 03 Jul 2020 at 20:28
Sorry - previous reply was for Mike, not Ken !

Dohhh
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Brian UK Quote  Post ReplyReply Direct Link To This Post Posted: 03 Jul 2020 at 22:07
Running hot would normally suggest retarded ignition, but it could also be a weak mixture.
Brian.

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Post Options Post Options   Thanks (0) Thanks(0)   Quote Perks Quote  Post ReplyReply Direct Link To This Post Posted: 04 Jul 2020 at 07:59
Hi Brian,

Thanks for the post, I think it's more likely the ignition as the plugs are quite sooty - particularly the one which is running hotter.

The mixture screws are out about 2.25 turns at the moment.
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Ken-Guzzibear Quote  Post ReplyReply Direct Link To This Post Posted: 04 Jul 2020 at 09:46
Both my guzzis one carb/points the other FI will have one side go cherry red within a short time on choke/tick over, i found on the V1000 the carbs are often slightly different settings each side it is a juggling act, sounds like the timing is good, did you put a wee bit of lube on the adv retard mechanism? I always followed the advice to file out the lower points set to get full adjustment there is a guide to setting these up by Pete Roper .... thing is as many find out setting up a big Guzzi will have many variables in fact with the "lash" in the timing chain and the variances in points etc even setting it spot on to the "book" can leave well frustrations if ever the old adage ...move it just a gnats was true .... Now you have the timing set, double check the points, but look on top of what was a rotor arm on the distributor that notch was for a rotor arm, you can get the points set by eye .... so that then leaves really the carbs .... yes new head gaskets will need torquing down after 1-200 miles again at 600 then 1200 once there is no movement they are good, old school engineering .... might be you need to run it about to allow it all to settle down .... 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Perks Quote  Post ReplyReply Direct Link To This Post Posted: 04 Jul 2020 at 17:42
Hi Ken,

Thanks again for even more useful info. I'm going to spend tomorrow having a play about with it.

I did lube the dizzi when I was setting it up a short while back, and I checked the advance mechanism was free to move easily.

I read somewhere some long time ago, I think it could have been a Gregory Bender article, to set the mixture on the RHS carb a quarter turn richer than the other.

You're right, the bike needs a good shakedown as it's been off the road for years. I'll re-torque the heads and re-set the valves and check the points and give it a good run and see what happens !

Thanks again for your help, it's really appreciated.

All the best,

Perks 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Perks Quote  Post ReplyReply Direct Link To This Post Posted: 09 Jul 2020 at 11:45
Hi Ken,

Good tip on re-torquing the heads. Was surprised that I managed to get over half a turn on each head bolt after just a few minutes of running.
Valves re-adjusted and re-checked the timing, which was a little out between the two sides. I matched them up and advanced both a little.
It seems to be running a bit better. Just need to take it for a proper run and get my Carbtune on it.
Little by little it's getting there, with help from the forum.

Thanks all 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Ken-Guzzibear Quote  Post ReplyReply Direct Link To This Post Posted: 09 Jul 2020 at 17:09
glad to help, forgot to re do mine result blown head gasket never forgot again 1st check literally after start up 2nd 600 mls 3rd 1000 once they do not move all good 
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Post Options Post Options   Thanks (0) Thanks(0)   Quote Perks Quote  Post ReplyReply Direct Link To This Post Posted: 14 Jul 2020 at 20:47
Thought I'd sorted this, then I lost sparks on one pot and then after it ran on only one, I lost both !

Checked across the points with a test light earthed on the engine case. With the ignition on, I'm now getting the bulb illuminated all the time, no matter where the flywheel is. Before this I was only getting light when the points opened.

It seems like something must be shorting out somewhere, but I can't fathom it out.

Could it be a dual coil failure ?

Scratching my head here !!!!

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