1988 Ducati Paso 750 timing belt idler bearing part number

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murphus
Posts: 51
Joined: Wed Jun 24, 2020 6:27 pm
model: 750 Paso
year: 1988
Location: USA

1988 Ducati Paso 750 timing belt idler bearing part number

Post by murphus »

Does anyone have an alternate part number for the timing belt idler bearings for an '88 Paso? The original bearings are FAG 63018, but that part number no longer appears active, even on the FAG site. Looks like the factory part number bearings (751710827) are available from Ducati dealers, but they're kinda stupid expensive at something like $45 each. By contrast, the timing belt tensioner bearings are a standard 6201. I can get quality Koyo replacements for $6.61 each.
For the idlers it uses 4 total, 2 in each idler, with a sleeve. And for that matter, has anyone ever replaced said bearings? I don't see any sort of stop/clip to limit/set installation in the sleeve. I can measure of course, just curious.
1973 BMW R75/5
1974 Laverda SF2
1976 Suzuki GT185
1983 Lavarda RGS 1000
1988 Ducati Paso 750
1995 BMW K75
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paso750
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Re: 1988 Ducati Paso 750 timing belt idler bearing part numb

Post by paso750 »

according to the pic in this ebay auction it's a SKF 630/8-2RS1.
https://www.ebay.com/itm/OEM-NOS-Ducati ... 2460162617
Same here:
https://www.ducaticlassics.com/ducati/7 ... 80x220x110

The specs: https://www.skf.com/us/products/rolling ... 0%2F8-2RS1

I'm guessing you have the bottom belt idler. There's a circlip in the middle (#33).
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murphus
Posts: 51
Joined: Wed Jun 24, 2020 6:27 pm
model: 750 Paso
year: 1988
Location: USA

Re: 1988 Ducati Paso 750 timing belt idler bearing part numb

Post by murphus »

That looks like it, thanks! I'd just done a quick measurement before your reply and the specs line up. My comment about whether there's a limiting stop were made from a faulty memory that the bearings were inset from the outer face of the sleeve; they're not. I'm going to hope I'm right in assuming they'll simply press out and back in. Looks pretty straight up.
1973 BMW R75/5
1974 Laverda SF2
1976 Suzuki GT185
1983 Lavarda RGS 1000
1988 Ducati Paso 750
1995 BMW K75
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paso750
paso grand pooh-bah
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Re: 1988 Ducati Paso 750 timing belt idler bearing part numb

Post by paso750 »

not sure how to get them out with the circlip between them
murphus
Posts: 51
Joined: Wed Jun 24, 2020 6:27 pm
model: 750 Paso
year: 1988
Location: USA

Re: 1988 Ducati Paso 750 timing belt idler bearing part numb

Post by murphus »

Good point; me either. I have a blind puller, not sure if I have an adapter small enough. Maybe heat up the sleeve first? Be nice to see inside a blank sleeve to see just how it's made.
1973 BMW R75/5
1974 Laverda SF2
1976 Suzuki GT185
1983 Lavarda RGS 1000
1988 Ducati Paso 750
1995 BMW K75
murphus
Posts: 51
Joined: Wed Jun 24, 2020 6:27 pm
model: 750 Paso
year: 1988
Location: USA

Re: 1988 Ducati Paso 750 timing belt idler bearing part numb

Post by murphus »

Looking at the parts diagram, it would appear to show two different idler bearings schemes; one with the bearings in a sleeve (d.m.) and one with the bearings exposed (f.m.) Drawings in the factory repair manual (F.4) appear to show idlers without a sleeve. The part number for the bearings in both schemes is the same, sleeve or no sleeve, but the spacer has a different part number, depending upon which setup you're using. Both appear to be discontinued. I wonder if the only difference is the thickness of the spacer to make up for no clip between the two bearings?
1973 BMW R75/5
1974 Laverda SF2
1976 Suzuki GT185
1983 Lavarda RGS 1000
1988 Ducati Paso 750
1995 BMW K75
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paso750
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Re: 1988 Ducati Paso 750 timing belt idler bearing part numb

Post by paso750 »

on the first pages of the parts catalog it says:
F.m.: up to frame number ...
D.m.: from frame number ...

No idea what the frame number is. Can't find that info.

Removing the second bearing from the sleeve should be easy as soon as one is out.
When I had a similar issue with a bearing inside a piston I tried penetrating oil first. After a few hours I heated the piston up, sprayed it again and let it sit over night. Then I found a socket nut that fit on the piston and which was larger than the bearing. After taping piston and socket nut together I hit the nut on the table numerous times and after several attempts the bearing slowly moved out.

This is a pic of the spacer used on the belt idler w/o sleeve. (#22) Couldn't find one of yours.
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murphus
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Joined: Wed Jun 24, 2020 6:27 pm
model: 750 Paso
year: 1988
Location: USA

Re: 1988 Ducati Paso 750 timing belt idler bearing part numb

Post by murphus »

Ok, good info. Being a Ducati newbie "d.m." and "f.m." meant nothing to me; now I know. Problem is getting the first bearing out. There's really no visible space between the two, and since they both have the same inside diameter - and only 8mm at that - it's tough to get any purchase on the inner race. Heat seems necessary. For what it's worth, one set feels perfect, the other felt a bit gritty the first few times I turned it, but smoothed out. Bike hasn't run since approx. 2003. Old grease turning into little crystals?
1973 BMW R75/5
1974 Laverda SF2
1976 Suzuki GT185
1983 Lavarda RGS 1000
1988 Ducati Paso 750
1995 BMW K75
angelix
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Re: 1988 Ducati Paso 750 timing belt idler bearing part numb

Post by angelix »

there vare bearing pullers made specificly for "blind" aplications, this is not the exact case but they could work; there are many videos on the subject on youtube including some usning home made tools.

Knowing that you are going to replace them one way is to weld a nu6t on the inner race and push the bearing out from the other side, that could work.

what I would do? I would get the puller set or try to make a home made version , but then I love having tools for everything. :mrgreen:
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paso750
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Re: 1988 Ducati Paso 750 timing belt idler bearing part numb

Post by paso750 »

There's a washer between the two bearings. If you can manage to move that a bit you may be able to get to the inner race.
murphus
Posts: 51
Joined: Wed Jun 24, 2020 6:27 pm
model: 750 Paso
year: 1988
Location: USA

Re: 1988 Ducati Paso 750 timing belt idler bearing part numb

Post by murphus »

Thanks for the tips/insight. Might go a different direction. I've checked the overall specs of the fixed pulley for later 2-valve engines and it looks like one can simply update. It's 1mm shorter and 1mm larger OD, which shouldn't cause any issues. Bevel Heaven sells the Flennor 45120211A-Z for $49.74. My local bearing shop quoted me $25 each for the SKF bearings, so it's a wash cost wise, and and easier install -- assuming it works. I'll post back when I know more.
1973 BMW R75/5
1974 Laverda SF2
1976 Suzuki GT185
1983 Lavarda RGS 1000
1988 Ducati Paso 750
1995 BMW K75
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