Since I bought my MK1 stag 8 yrs ago it has suffered from a jumpy erratic speedo reading,a range of about 10 mph,ie at 50 would read between 50 and 60 mph.
I haved picked many brains on this subject,and the answers I have got have always been cable based,ie you need to regrease,are there any sharp bends in the routing etc.Having checked both was at a loss aaprt frrom sending the speedometer off for refurbishment at a cost of £65 upwards depending on supplier.
Well Iam pleased top say I have fixed this myself and it feels great to give a tip back to the forum after the many I have benefited from.
I borrowed a scrap unit to take apart andpractice on.What I found inside was that the 2 main moving parts,ie a vertical brass worm running on to a horizontal plastic gear,on the scrap unit the two afore mentioned items seemed to be well lubricated.
Took mine apart and the same parts appeared dry.I carefully used a drip of WD 40 onto the spindles of both parts,using the red straw for accuracy,whist holding the unit in a way so that any excess would fall away rather than running into the unit its self.
Could not believe the improvent on testing,still a little jerky on the 10-20 mph on slowing down but once upto speed say over 30ish,very good.
So unless there is a more sinister fault inside the unit,I would certainly class this as a worthwhile solution before sending off for refurb.
This of course all comes with caveat that there is no substitute for proper calibaration
and would not provide any sort of accuracy improvement.
Hope this helps someone,
Regards Mark
I haved picked many brains on this subject,and the answers I have got have always been cable based,ie you need to regrease,are there any sharp bends in the routing etc.Having checked both was at a loss aaprt frrom sending the speedometer off for refurbishment at a cost of £65 upwards depending on supplier.
Well Iam pleased top say I have fixed this myself and it feels great to give a tip back to the forum after the many I have benefited from.
I borrowed a scrap unit to take apart andpractice on.What I found inside was that the 2 main moving parts,ie a vertical brass worm running on to a horizontal plastic gear,on the scrap unit the two afore mentioned items seemed to be well lubricated.
Took mine apart and the same parts appeared dry.I carefully used a drip of WD 40 onto the spindles of both parts,using the red straw for accuracy,whist holding the unit in a way so that any excess would fall away rather than running into the unit its self.
Could not believe the improvent on testing,still a little jerky on the 10-20 mph on slowing down but once upto speed say over 30ish,very good.
So unless there is a more sinister fault inside the unit,I would certainly class this as a worthwhile solution before sending off for refurb.
This of course all comes with caveat that there is no substitute for proper calibaration
and would not provide any sort of accuracy improvement.
Hope this helps someone,
Regards Mark