TomB Posted September 8, 2011 Share Posted September 8, 2011 Does anyone have a new/ nearly new set of Piper Vernier pulleys and they could measure the tooth depth? Im keeping an eye on mine as they have done about 35-40k miles in my 7, and I bought them secondhand a few years ago. The red colour has long worn off leaving the silver alloy. There are no significant grooves on the running surface of the pulleys that I can feel with my finger, but dont want a cam belt to slip! The teeth are about 3mm deep on my pulleys - is there a wear limit set by Piper? Link to comment Share on other sites More sharing options...
Wrightpayne Posted September 9, 2011 Share Posted September 9, 2011 Tom, I'll check tonight - I have a new set gathering dust in the garage at home. Ian PS - Planning to use them next year so not for sale 😬 Link to comment Share on other sites More sharing options...
TomB Posted September 9, 2011 Author Share Posted September 9, 2011 Cheers! Im thinking I might replace them when I do the cam belt & tensioner over winter - but if they are not considered worn much, I wont. Im 'only' running a standard Supersport cam engine, so not mega cam & spring set up, so I hope they are OK. Link to comment Share on other sites More sharing options...
Leadership Team SLR No.77 Posted September 9, 2011 Leadership Team Share Posted September 9, 2011 Tom, I have a brand new set if you want to compare. Stu. Link to comment Share on other sites More sharing options...
simonpa Posted September 9, 2011 Share Posted September 9, 2011 I've heard of 2 cars recently where the belt has slipped and caused damage (new head needed in the latest case). Oily may be able to confirm if this is a known problem on higher mileage installs? Cheers - Simon Link to comment Share on other sites More sharing options...
TomB Posted September 9, 2011 Author Share Posted September 9, 2011 Simon, that precisely what Im trying to prevent. Ive heard tale of them wearing faster than standard pulleys. I need to know whats the new depth if to try and gauge how much mine may have worn. If they havnt worn, my pocket money can be spent elsewhere on the car! Stu, please can you measure the tooth depth with some vernier callipers? Link to comment Share on other sites More sharing options...
Leadership Team SLR No.77 Posted September 9, 2011 Leadership Team Share Posted September 9, 2011 Can do Tom, and the overall diameter measurement may be more useful also. You know what the result is going to be though ☹️ Maybe for the future consider an offset dowel arrangement using standard pulleys - I'm thinking about swapping to this when my 1800s running again so the verniers can be used on my 1900. I think Dave H was also thinking about going this route due to the chocolate nature of verniers - for a more road-focused 7 using the timing belt cover it may be a better alternative. Stu. Link to comment Share on other sites More sharing options...
TomB Posted September 9, 2011 Author Share Posted September 9, 2011 I never though of the OD or comparing the verniers with the original pulleys. I should have some standard pulleys somewhere to compare them too. I think the newer Piper pulleys are main of tougher Dairy-lee. Link to comment Share on other sites More sharing options...
6speedmanual Posted September 9, 2011 Share Posted September 9, 2011 I think you also need to pay attention to wear on the flanks of the cog teeth. They wear on the drive face resulting in them going out of pitch, which starts to gnash away the teeth on the belt faster than normal. Peter Link to comment Share on other sites More sharing options...
Simon Owen Posted September 9, 2011 Share Posted September 9, 2011 Hmmm ... I wonder how much better the new verniers are than the original ones ? I think Dave H went full circle and ended up fitting a new set of Piper ones in the end. Oily may have some comments on this .... Link to comment Share on other sites More sharing options...
Jason Plato Posted September 9, 2011 Share Posted September 9, 2011 . I wonder how much better the new verniers are than the original......... not much - they are hard anodoised but still like cheese ... Link to comment Share on other sites More sharing options...
Wrightpayne Posted September 9, 2011 Share Posted September 9, 2011 Brand new verniers... 2.9mm depth though calipers wouldn't go to very bottom of groove. 120.5mm overall dia. Ian Link to comment Share on other sites More sharing options...
TomB Posted September 9, 2011 Author Share Posted September 9, 2011 120.5mm overall dia. Presumably including the tooth, not taken groove to groove? Hopefully Ill be able to measure with them on the engine. Groovy man, thanks very much . Will check after Tesco PS - I think Dave H went off-set dowels. Link to comment Share on other sites More sharing options...
Wrightpayne Posted September 9, 2011 Share Posted September 9, 2011 thats max OD. just thinking another important measurement might be width of tooth which is 3mm Ian Link to comment Share on other sites More sharing options...
Englishmaninwales Posted September 9, 2011 Share Posted September 9, 2011 I took this issue up with a well known supplier a couple of years ago and I was told it was fair wear and tear.....blamed me for running without a belt cover and letting dust accelerate wear. That was before he asked me whether I'd run without a belt cover Poor quality IMO. Link to comment Share on other sites More sharing options...
TomB Posted September 10, 2011 Author Share Posted September 10, 2011 Been in to the garage this morning with my vernier callipers and measured OD twice at 90o to each other, and the depth at 180o Inlet: OD 120.3mm & 121.01mm / Tooth depth 2.9mm & 2.84mm Exhaust: OD 120.8mm & 120.6mm / Tooth depth 2.7mm & 3.1mm Tooth width, near as dammit 3mm. As the measurements where taken on the car with belts etc in the way, they might not be perfect, for example the depth measurements were taken at a slight angle due to the rear cam belt cover, and as with Ian's measurements, the caliper extension wouldn't go quite to the bottom, but they are representative. There is still some red in the bottom of the tooth grooves. Ill repeat the measurements when the belt is off and check the running surface of the teeth for flatness, but for now Im thinking I probably wont need to replace them this winter. Link to comment Share on other sites More sharing options...
Leadership Team SLR No.77 Posted September 10, 2011 Leadership Team Share Posted September 10, 2011 Brand new (black anodised) set .... OD 120.4mm Tooth depth 2.9mm Tooth width at crown 3.1mm Link to comment Share on other sites More sharing options...
simonpa Posted September 10, 2011 Share Posted September 10, 2011 I agree with Peter - the main considerations are likely to be the leading edge and top corner. If these are sloping/rounded, then slippage is more likely to occur. The cogs may wear more than the belt as the belt has more overall teeth and it's flexibility will protect it. The belts action on the teeth of the cogs will act like sandpaper. If you have a decent-ish camera, then a close-up shot of the teeth might show the wear. There might be close-ups of new verniers on t'web.. Cheers - Simon Link to comment Share on other sites More sharing options...
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