Ok, so this is probably a bit of a dumb question.. I've had a quick search on the forum, but can't find an answer, so would appreciate an answer, or to be pointed in the right direction as I'm probably the 300th person to ask this one... Looking for advice on threads Ducati uses on bolts / fasteners. I assume this hasn't changed over time, my question specifically relates to a 1995 750SS and a 2000 748R. Do the Ducati thread pitches vary with the fastener size or do they use 1.25 threads on M6 -> M10 bolts as stated on some titanium fastener sites? Other references say the thread pitches are as follows: M5 x 0.8 M6 x 1.0 M8 x 1.25 M10 x 1.25 I'm looking to order a variety of stainless bolts and don't want to get the wrong sizes. Anything else I need to know? Thanks in advance, Nick
Apart from the M10 which should be 1.5, the sizes you show are 'standard' metric threads and with regard to the SS, I didn't find any variations on standard, even down to the countersunk M4 in the tops of the master cylinder caps. If you are getting inside the engine, you will find there are things like M10 x 1.0.........but then you won't be using stainless in there, will you? Brake line unions will also vary... AL
Thanks for the quick answer, that was what I suspected. Another related question, are there any applications where I should avoid stainless bolts on the bike due to tensile strength? I imagine the rear shock mountings would be one? Not planning on splitting the engines. Thanks
With stainless you should be more concerned with the sheer strength, so don't use stainless on brake discs. Having said that, I have stainless in my shock mounts simply as an experiment....and as I like my rear shock set quite hard.....well, 200 miles so far so good. I also have stainless in calipers, yokes, forks and swingarm.........most have been there about two years. AL
Not sure if its a recent thing but I did find M10 fine used on the sidestand I think on the 1098, std Metric but fine, so there are one or odd ones although they are pretty rare. The vast bulk are as Arquebus has stated. I usually just take the bolts out one at time for the ones I plan to replace and measure them. Get yourself a Metric thread gauge cheap as chips and excellent wee tool for checking this sort of stuff. I hate measuring and counting threads and always find the results a bit hit and miss. John
Here's the crunch, then........sidestand on the SS uses two M10 x 1.5............So we can't always assume everything is the same....
http://www.stainlessmiddleton.co.uk/productlist.php?category=Screwpitch Gauge&subcategory=Screw pitch guage
Rear sprocket nuts are M10 fine. Thats about the only anomoly I have spotted, but there may be others.
I did preface it stating I wasn't sure if it was a recent development or not. Profound apologies & grovelling email written in blood to follow. Jeez................I'll get ma coat John
M10 x 1.25 correct for the SS it seems..............they refer to the sprocket in the workshop manual as Ring Gear........I think that's what they mean.
Thanks all, it sounds like the general bolts are standard threads, but worth checking the caliper bolts etc. Looks like a thread gauge might be a good investment.
Nope, normal M10 on the SS.............. The workshop manual also gives a list of bolt / nut sizes at the back in the torque settings section.
Why? Get an ordinary M10 nut and try your M10 bolt in it.............if it doesn't fit the nut it is probably an M10 x 1.25.............but the caliper bolts are standard M10 on the carbed SS.
I have had S/S bolts on my 748 and 916 discs since the 20th Century. Never had a problem with the shear strength. R
ProBolt advertise stainless steel bolts specifically for brake discs and calipers, so presumably they do not think the shear strength is a problem.
No, you are wrong about the disc bolts. Application of the brakes applies a tangential force to the disc to react the torsional load from the tyre. The tangential load is reacted at the interface between the disc and wheel hub. The force is reacted equally by each of the 5 or 6 disc bolts as a shear load. There is no tensile load applied to these bolts - a tensile load would be one that would be due to the discs being forced sideways (along the same axis as the wheel spindle) which does not happen (on my bikes). R
