Over Stressed Cobra

You may recall my 1968 T500 Suzuki Cobra build which was detailed here back in 2014. Once on the road, while the bike ran fine, I was unhappy with the front brake as it juddered and no amount of adjusting of the brake shoes and the brake linkage seemed to fix it, so off it came for a closer inspection. You may well imagine my surprise at finding a series of fine cracks in the cast iron brake liner ! Not good, and definitely the sort of thing that could seriously ruin your day.

This generation of front hub was well-known for cracking, but on the right side plate which I had inspected closely. Admittedly this sort of side wall failure seemed to happen in racing applications where the side stresses are obviously higher than what you would normally expect to encounter, but I had never heard of the liner itself cracking. You can see one set of cracks in the photo below.

The only fix was to replace the entire front drum and so the Cobra was parked in the shed till I could find a replacement. That took a little while, and then as is often the case other events got in the way, so it continued to occupy the ‘I’ve been a very bad boy’ corner of the garage till this year when I decided it really needed to get a bit of use.

While it had been sitting I had decided to have the original wheel rims re-chromed. I had replaced them with new rims when I first did the rebuild. These new rims were from Suzuki, but the original supplier  (Takasago) had changed hands and now the rims came with the new manufacturer’s name ‘Excel’ prominently stamped into the side of the rim, which frankly bugged the heck out of me. The original rims had the correct date stamp for the year of the bike (take a look at this link on how to date your Suzuki) and so it made sense to me – if not to anyone else – to put them back on. While I was at it, I also ordered some stainless steel spokes from Buchanan’s in the USA. I’m hoping SWMBO’d will never see the final total cost !

Today I got it all back together and will take it for a ride tomorrow, and while I’m sure there will be other issues still to be sorted, at least I am reasonably sure the front hub will not be coming apart due to stress cracking ! 🙂

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