Had a bit of free time today and tried to create my own 26mm holding tool for the cam belt tensioner on my 999. It is based around a 24/26mm double ended box spanner. The handle is made from a piece of tubing I already had with a captive nut in the end and a suitable bolt. The black shading on the bolt head shows what needs to be removed to give more clearance inside the box spanner. Bolt screwed into captive nut. Box spanner cut in half (26mm), modified and shortend bolt. Here it is assembled The hollow allows a suitable sized socket to get onto the locking nut. Does it work? Don't know, as my belts aren't due for changing yet. If some 749/999 owner wants to test it, then PM me and I'll post it out on loan.
Excellent work Chris Is the box spanner sufficiently short enough to fit in the gap twixt the frame tubes on the vertical cylinder ( it looks too long to me!) I think a refinement would be to weld a handle on to the box spanner at an appropriate angle, then that would be easier to manipulate in the small space available. I would have thought the head of the bolt would prevent the insertion of a 12mm socket , hard to tell from the scale of the photo though I have just been modifying a 26mm combination spanner with an off hand grinder, got it home and it just needs a few more thou' ground off and it should all be good. I would be happy to trial the tool for you. If you are agreeable I will pm you my address and I will see how it works as I have all my engine exposed. Will post it back when finished. I'm still awaiting 2 Fuji nuts , hopefully should be here very soon.
I was just saving time using some bits I had in the garage. I originally intended to cut it much shorter and weld a handle onto it. The frame gap may be problematic on the vertical though. The already present hole in the box spanner presented an opportunity to use it for the handle. May have to go the welded handle route then' There is ample room to get a socket in as I cut the bolt head down, the tube is approx 26mm diameter. The wall thickness of the box spanner should fit into the recess of the pulley. Proof will be in the pudding, as with all prototypes. I'm not in a position to try it out at the moment though.
chris I have just done a measurement from the front face of the 26mm tensioning nut to the internal face of the frame tube, and it is 37mm, so I would say unless the overall height of the box spanner is less than that it won't fit in the gap.
Cheers for that. Looks like a MK2 version is required. I have 30mm of hex to play with. The socket wall is 2mm, will that clear?
chris The internal diameter of the recess in the pulley is 37mm. I did borrow a box spanner from a mate but it was a very solid thick walled job and didn't fit in the recess. It needs to be a thin walled box spanner!
chris I today finished off the grinding off my spanner and it fits a treat. Now I have actually used it to finally at long last fit my belts I can say that it's definitely the way to go. I took it into my nearest Ducati dealership today as I was picking up the Fuji nuts and showed it to the mechanics there as I was interested to see what they used. They told me it was a huge improvement over what they used ( didn't find out exactly what it was ) but the mechanic was impressed. I took great care to ensure that I got exactly 110Hz on both belts, and checked and checked again and only when i was satisfied did I finally tighten the locking nuts and then checked again that all was in order. However once I turned the engine over many times I checked the frequency again and was surprised to find that it had now dropped to about 95Hz on both cylinders. I am putting that down to the belts settling in for the moment unless some wise person can inform me otherwise.
You have tensioned the belts, from slack, in one place. Rotating the engine allows the tension of the belts to even out around the run. ie, takes out the tight spot where you tensioned.
Thanks Would you think the reduction in tension down to about 95Hz is about right, is this why the original spec' of 110Hz is stipulated as it's known that they will fall to about 95Hz once the tension has evened out?
You should have a setting figure and a figure after the belt has turned. They would never be the same value.
That makes perfect sense to me. Unfortunately this is the first time I have done a 4v so am in unknown territory as to what the tension might reduce to after turning the engine over and evening out the tension.
When I fit belts, to anything, I assemble them over tight and then turn the motor over 8 times. This gives the belts a chance to align on the pulleys and settle down and leaves the front pot at TDC. Then I tension. I always tension down from tight, rather than up from loose to. Don't forget to turn the motor three quarters to get the rear pot to TDC as well after doing the front. The hz reading will always read lower once the motor has run. The initial set is what matters.
Understood Neil, thanks for your input, much appreciated. btw I turned the engine backwards 90' after tensioning the horizontal cylinder, and checked with a rod inserted in the plughole that I was definitely at TDC,which was confirmed as well by the slots in the end of the camshafts being in a horizontal position as per the Ducatitech video. I presume this is correct?
I always tun the motor forward by 270 degrees...... old habit to achieve the same thing really. Comes from cam timing so there's no error taking up the back lash in gears etc.
You've designed a tool.....................without checking details of the job it's going to do...........guessed the sizes.............sawn the spanner in half badly............used low grade materials................and said it doesn't work..............then gone public..................asked for beta testers................. it's hardly a recipe for success is it? is that valued input?
