175TS with 125S engine project

Ducati single cylinder motorcycle questions and discussions, all models. Ducati single cylinder motorcycle-related content only! Email subscription available.
Moderator: Morpheus

Moderator: ajleone

George
Posts: 110
Joined: Fri Feb 14, 2020 2:51 am
Location: Essex UK

Re: 175TS with 125S engine project

Postby George » Mon Jun 22, 2020 9:36 pm

Thanks for replies piston two oil rings. My Moto Guzzi 125 single from the 1960s also had two oil rings maybe an Italian design for those times. As pistons have run for many years with two rings I am going to fit both, why change what works.
George Essex UK

George
Posts: 110
Joined: Fri Feb 14, 2020 2:51 am
Location: Essex UK

Re: 175TS with 125S engine project

Postby George » Thu Jun 25, 2020 6:14 pm

While waiting for rebore and new conrod fitted I have attempted to set up Mototrans head bevel gears. I still cannot see how this can work and would appreciate any help to understand set up.
I have added a sketch to help explain my problem.
The recess in the top tube flange is deeper than the lip on the bearing housing allowing the housing to move up and down even without gasket fitted. There seems to be no positive way to grip housing allowing it to move up and down about 2.5 mm. Should the housing be a tight fit in head and held in place by this tight fit. This does not seem a good idea.
I can fix bevel shaft position in housing via shims but cannot fix position of housing in head or stop it turning. What am I doing wrong?
Attachments
Scan.jpg
George Essex UK

Duccout
Posts: 399
Joined: Wed Feb 05, 2020 1:20 pm
Location: Essex UK

Re: 175TS with 125S engine project

Postby Duccout » Thu Jun 25, 2020 6:23 pm

Hi George,

I only know about the later bikes, they have a top bearing flange that is slightly recessed when fitted, and the top of the bevel tube has a protruding ring that goes against it and holds it in place, so I also don't see how yours can work. Could it need shims fitting between the top flange and bearing housing?

George
Posts: 110
Joined: Fri Feb 14, 2020 2:51 am
Location: Essex UK

Re: 175TS with 125S engine project

Postby George » Thu Jun 25, 2020 9:06 pm

When Nigel supplied replacement bevel tube he also supplied bearing housing with oversized diameter. Have had a measure up and will get this machined to suit.
George Essex UK

George
Posts: 110
Joined: Fri Feb 14, 2020 2:51 am
Location: Essex UK

Re: 175TS with 125S engine project

Postby George » Wed Aug 12, 2020 6:50 pm

Not posted for a while thought I would give an update. Because of the Covid lockdown things have taken longer to progress.Got my engine crankshaft and re-bored barrel back today so can start on engine rebuild.
Metalwork with painter and don't expect that back till end of September. Chromed parts should be delivered in next couple of weeks I hope.
While waiting I have refurbished wheels and brakes, heli coiled sump plug thread, refurbished seat. Cover made by local company. I cleaned and painted frame, made new foam base and fitted it all together.
George Essex UK

Duccout
Posts: 399
Joined: Wed Feb 05, 2020 1:20 pm
Location: Essex UK

Re: 175TS with 125S engine project

Postby Duccout » Wed Aug 12, 2020 6:59 pm

Great stuff George! Did you helicoil the drain thread yourself? How difficult was it to do a thread that large?

Colin

George
Posts: 110
Joined: Fri Feb 14, 2020 2:51 am
Location: Essex UK

Re: 175TS with 125S engine project

Postby George » Wed Aug 12, 2020 7:16 pm

Hi Colin. Helicoil not to difficult. Drilled hole by hand without putting to much pressure on drill. same with tap. Had to cut coil down as hole is not very deep. As the son of a Yorkshire man the hardest part was parting with £85 for the kit. I now have four spare helicoils if anyone should need one.
George Essex UK

Duccout
Posts: 399
Joined: Wed Feb 05, 2020 1:20 pm
Location: Essex UK

Re: 175TS with 125S engine project

Postby Duccout » Wed Aug 12, 2020 7:53 pm

I know that helicoils are not cheap, but it would have been dearer if an engineering shop had done it.

ranton_rambler
Posts: 281
Joined: Sun Jun 04, 2017 11:33 am
Location: Stafford UK

Re: 175TS with 125S engine project

Postby ranton_rambler » Thu Aug 13, 2020 11:16 am

I thought you'd been quiet George.

I've just decided to sort my seat too, although it's a different design with no foam in it. Looks like a sheet of thick-ish rubber over the sprung base with a vinyl cover stitched onto it. I reckon I could make a new cover but I don't think Madeleine's sewing machine would cope with the rubber.

Will call in to upholstery place in town tomorrow to see what he thinks.

Ian

George
Posts: 110
Joined: Fri Feb 14, 2020 2:51 am
Location: Essex UK

Re: 175TS with 125S engine project

Postby George » Thu Aug 13, 2020 11:40 am

I placed a sheet of 1.5mm soft rubber over springs, but not down sides,to stop springs wearing foam then made foam Base 2" thick and covered with good quality vinyl secured to bottom of frame. Feels firm but comfortable.
George Essex UK


Return to “Ducati Singles Main Discussions (& How to Join)”

Who is online

Users browsing this forum: No registered users and 24 guests