There are many many factors in the choice/design for belts. Even down to pulley diameters, engine firing pulse, temperature, belt speed, belt width and cam operating force to name a few. I think Chris Kelley from CA Cycleworks did an appraisal on Ducati belts whilst designing the Exact belts. Although I can't find it at the mo. It detailed aspects of belt design and load testing
Rock on mate .... more power to you ! Ignore the nay-sayers .... what you are doing is on the path to all knowledge . Thinking and theorizing , testing and observing , and then modifying your hypothesis accordingly . There's a whole lot of crap talked about belts , right across the auto industry , and a fair few folk who have some skin in the game .... ie. mystifying , obscuring and encouraging paranoia .... ..... which is often seen as a help to boosting the bottom line . I'll be eager to read whatever you discover .... keep on posting !
I would never want to discourage empirical learning, but honestly, with the scope and purely qualitative nature of your proposed test, you may as well just look at the edge of new Gates Ducati / Renault belts and see if the reinforcing layer appears the same colour, weave pattern, strand size, and construction. Worth noting, apart from all the other engine differences, Renault use springs to control their valves, which sets up a very different torque load pattern on the belt. Ducati torque load on belts is small in comparison, but the engine design and use pose a different set of challenges.
The Gates Renault belts are about 11 pound each. Obviously it isn't worth spending thousands of pounds on a analysis to save 90 quid every 2 years. I disagree with some views that every belt was especially designed for a specific purpose. In my view, based on my personal professional experience, most companies would look towards a existing mass produced product rather than going bespoke. It makes commercial sense. I'm using the gates belt with no problems. When I compared them visually with the OEM belts I took of, they are identical as far as I was able to tell. They look the same including the colour of the reinforcement fibre, feel the same, tooth profile is the same as best as one can tell with standard measuring equipment like verniers and radius gauges. It makes very little sense for Gates to produce a near identical product to another of their range where a mix up would leave them vulnerable to all kinds of problems, law suits, bad press etc. Unless the cost of the materials for the Ducati belt is vastly different to the cost of the Clio belt it makes zero commercial sense to produce them separately. It makes more sense to make both to the higher spec and just brand them as required. Through my use of the cheap belt I'm satisfied that the length, stretch, tooth profile are good. The belts look new after 3 years although with little milage. I haven't found anything that convinced me that the gates belt is anything but the same as the OEM. People tell me there were extensive studies on the subject but can't remember where they have seen it or that it is classified. The standard comments I can find is either people like me saying they had no issues or people saying oh wouldn't risk it, always use OEM. Many many other parts are not made specifically for this bike or that bike. Solenoids, fuel pumps, filters, connectors, bolts, spark plugs, even ECU hardware. The list goes on. Anyway, what motivates me? Honestly, I was hoping for a used OEM belt as I didn't keep mine. Had I kept them I would not have started this discussion. I'm going to try and find out if the reinforcement belts of OEM and Gates are made of the same material. Depending on how successful I am in extracting intact fibres from both belts I will decide on the best way to test them. In any case it will be force v displacement to destruction. If I can get good data and repeatability either showing they are the same or not the same then I know just for myself if I use Gates Clio again or if I buy OEM. The reason I do this is because I can and it interests me. If at the end I have something I feel is worthy of sharing, good or bad I will do that but it isn't something that is important to me and I'm sure no matter what I will publish there is going to be mainly people telling me I've done it wrong or didn't look into slip angle or temperature or friction coefficient or I didn't do a thorough molecular analysis and other, excuse my German, Scheiße, and that is fine. These forums tend to do that. The good news is that a member has offered to send me a OEM belt and I will have hours of fun doing experiments. I will undoubtedly spend more than a set of belts worth of pennies to do it.
I wasn't referring to any particular post or reply today or any other day, it's just what happens. I'm not clever enough to even understand most of the points you made never mind understand them in a particular way. I didn't mean to cause offence and I certainly didn't take offence. It's just that some of the suggestions here and in other threads across the platform would need the funding and capability of the Max Planck Institute of Science to take on board.
You pretty much said what I said in your synopsis of what people will say on't tinternet - I really did think you were going to come back and say you were a molecular scientist as I was typing . Anything to do with automotive high performance engines is not off the shelf and is specified and developed along with the suppliers help. If your not a molecular scientist what do you do? I'm in automotive manufacturing and work as a technical feasibility manager in automotive design whatever that means (don't really want to find out) but what I say is from experience and not hearsay
Definitely interested in the results (fwiw) of this one. I use Gates belts as well ($56 vs $187 for Exactfit in my neck of the woods) and considering how few bikes use the oem ones, have also debated why Gates would spend the considerable cash to retool their equipment for such a low volume. It makes no sense to do so, but makes a lot of sense to tell people they do.
And if you are German, as you intimate above, your written English is excellent and better than a lot on here
8 years and counting, best job in the world. I used to work in Formula 1 most of my professional life including a number of years in a RnD department
I was being polite, didn't want to offend any on here, we all know what happens when that starts...... Thank fook some of the emojis have been eradicated.
I'm sure CCW did some empirical pull-test videos. I seem to remember that they were lifting the back of a truck using various belts. Interesting background viewing Akorenika - I think it was fairly easy to find - Google 'Exactfit belt test'
