1968 Cobra

[Alan H]

Regards OEM rims (or not), I had a stainless rim with stainless spokes put on the back of the 550.
I'm not concerned about the rivet counters - I intend building a rider.
Lots of SS bolts on the bike too, I think it looks OK, and that's what counts.
I've got a couple of words for anyone who doesn't like it and picks fault with the rebuild, second one's 'off'.

If anyone wants to build an exact copy of the original, then good for them. Just not for me I'm afraid.
I'm not prepared to pay over the odds for something that (to me) doesn't make any difference.

[oldjapanesebikes]

I'm not concerned about the rivet counters - I intend building a rider.

Excellent ! But you miss the point of this specific thread Alan - it's called 'Restorations' for a reason eh ? Like you I have a few 'daily riders' which I modify to suit me and to just use. But then I also have a few where the intent is to match how they looked coming out the factory as nearly as I'm able. Two different objectives - and two often overlapping, but different discussions.

[Sandman]

Regarding re-chroming original steel rims for an original restoration- I've come across a few issues you all might encounter. My first choice is always to refinish the original rims and spokes, as aftermarket items always seem to lose something critical in translation.

First is hidden internal corrosion that's caused by moisture held by years of contact with the tire bead surfaces. You might think your rims aren't too bad until you remove the tires and look closely inside.

Second is chrome platers who over polish the stripped rims at the raised or domed areas where the nipples come out. I've heard of them being thinned out so badly that wheel lacing causes the nipples to pull right out through the rim! Imagine the frustration and wasted money...

Third is polishers that erase names/logos and size numbers stamped on the rims, such as DID, TAKASAGO, 2.15 X 18. I've left rims off at platers and specifically asked that original numbers and letters be left as is- "yes, no problem". Come back, look at completed rims and can't find any details, or a just a faint ghost image is left. Thanks for just devalueing my original parts and taking my restoration down a notch, and paying top dollar for it! Problem is that the polisher doing the preparation doesn't speak English, and just grinds away- doesn't know or care. How can you communicate your specific restoration needs if the worker doesn't speak or read the same language? I've had original castings and details smoothed away/erased forever, and ending up looking like show chopper parts. Pick your chrome plater carefully, not by price alone- they're all expensive. FRUSTRATING!

Did I mention that my ex-plater always moaned about rising supply prices and passed them along to customers, yet has a brand new $55K Ford F150 Harley Davidson edition truck outside?

[oldjapanesebikes]

I've come across a few issues you all might encounter.

All excellent points - its always seems to be a bit of a crap shoot. We have one company here in town that the vintage British bike owners all use for their fuel tanks and rims and that they are happy with - but it isn't cheap, and as you mention rims have their own unique problems.

[argo1974]

I've have always been paying top money to platers but finally gave up due reasons mentioned by Sandman.
Last time an idiot erased the TAKASAGO name on the rims and completely polished sand cast shock nuts of my 69 Kawasaki H1.
Replacing the shocks did cost me around $250.
I do all filling, sanding and polishing myself now and only give the parts away for actual plating. The results are excellent.

[argo1974]

Ian, I wonder if could post a picture of the rectifier of your Cobra. I'm mainly interested in Sanken decal, though.
Thank you in advance.

Argo

[Sandman]

I do all filling, sanding and polishing myself now and only give the parts away for actual plating. The results are excellent.

Excellent idea- but how do you first strip away the chrome and get down to the bare metal base?

[oldjapanesebikes]

... a picture of the rectifier of your Cobra. I'm mainly interested in Sanken decal, though...

I'll check and revert in the next week or so.

[argo1974]

Excellent idea- but how do you first strip away the chrome and get down to the bare metal base?

This is possible with chemicals at home (HCl for stripping the chrome and HNO3 for stripping the nickel), but I give the parts away at chrome shop for stripping. Sometimes I use acid bath at home for tiny items though, but HNO3 is highly toxic.

[oldjapanesebikes]

I wonder if could post a picture of the rectifier of your Cobra. I'm mainly interested in Sanken decal....

Tough to get a good image with a flash - the letters are DA2/4B 8.2, but here you go:

[argo1974]

Ian, thanks a lot for the picture. The rectifier on my Cobra has the same letters and I'm sure now it's genuine. It is missing "G" at lower right edge though.

[oldjapanesebikes]

I just realised that in the stack of documentation I have, none of it covers the 34mm carburettors, and I'd like to check the float heights. The T500-2 shop manual doesn't mention the MK1, and I don't trust the information listed in Specifications Bulletin #11 that lists all the specifications for the 1968 models as it lists the wrong needle jet (P4 instead of Q5).

Anyone have a copy of a MK1 specific shop manual covering 34mm 'round bowl' carbs with the Q5 needle jet they could scan and post ?

Thx !

[oldjapanesebikes]

So the reproduction mufflers arrived from Marcel in NL - the shape is perfect.

Well - as it turns out I was wrong. My wife tells me that often, so perhaps sometimes its even true ! The shape is correct, the 'dimples' are in all the right places and the diameters are correct, but there are actually two issues that caused me a lot of phaffing about to sort:

• - the flanges/seams on the welds are fair too wide

• - the hanger mount on the muffler is off by about 4 or 5 mm (the old ones are about 33 mm off the centre line, and the new ones about 28 or 29 mm)

This meant that when mounted on the bike, the mufflers I received (I have no way to know if this is true for all the ones Marcel sells) were tight to the lower frame rail, and the lower weld flange was in the way of the side stand so it could not be mounted. In the photo below, the arrow points to an original muffler on the top and the lower weld flange/seam - you can see its almost non-existent. On the reproduction muffler below it you can see that the flange is quite wide and extends about 8 mm further than the one above.



To fix this, I shimmed out the muffler at the hanger using some stainless washers so that when bolted up it would just clear the lower frame rail, and I used a block of 9 mm stainless plate to shim the side stand so that the side stand pivot bolt can clear the under side edge of the muffler. That actually has a positive effect as it means the bike stands a bit more upright on the side stand now, so it isn't all a bad news story. And note that were I to do it all over again, I'd still buy from Marcel - they do look and sound fantastic and are a quality product, its just that 'some fitting is required'.

[GT750Battleship]

Hi Ian,following your Cobra story with interest,the pipes look very nice & it's good that they are available!! I've not seen or heard a GT750 run with the Delkervic Replica System,I do know that the guys in England were questioning "quality" control when they first came on the market ?

Cheers,
GT750Battleship.

[oldjapanesebikes]

Marcel's T500 pipes have the metal mesh tack welded inside the throat ahead of the first baffle, just the same as the factory ones, so the sound is the same. Weight is about the same also. I'm thinking of taking them off again as I'd like to replace the washers with some actual spacers - just a lot simpler to manage if you ever do have to pull the pipes off so you don't have washers rolling all over the floor. If so, I'll try to remember to take a photo of the inside.

The Delkevic pipes for the GT750 do not have that mesh, which is why they sound more like spannies. And the GT750 pipe sets have really come down in price eh ? $1295.95 USD for the full set now - it would be tough to get a set repaired and re-chromed for that kind of money.