Cobra Questions

[oldjapanesebikes]

Just something to know - the printed parts manuals I have all show this plate located on the inside of the top of the crankcase and show it for all models (1968 MK1 through to 1977 GT500). The fiche on the CMSNL site, the Ozbook site and Alpha-sports also show it. The on line fiche at http://www.powersportspro.com" onclick="window.open(this.href);return false; for the USA models show it, but also qualify it as only being in the R (1971) through M, but it was of course in the GT500 as well:



So when I started to put my MK1 cases back together I was looking at one of the printed parts listings I have as cross check, and initially wondered if I'd lost something - the early engines don't have the plate, nor is there anywhere to put one if you wanted to. The two 'bumps' you see in the photo below under where a plate would sit are the underside of the threaded holes in the casting for the oil line cover that mounts on the top of the case (and isn't used on the GT500's, but they didn't change the casting).

[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 just those pages ?

Thx !

[argo1974]

Ian, I went through the entire 1968 T500 service manual but couldn't find any hints for float height on VM34SC carbs.

[jabcb]

Am no expert, but two forum members discuss float height in this topic:
viewtopic.php?f=2&t=8532&p=130740&hilit=vm34#p130740

[oldjapanesebikes]

.. two forum members discuss float height in this topic

Thanks jabcb - I had read that thread also and will be trying a couple of different setups. but I had expected that there was actually a document in existence somewhere. Just seems odd to me that there isn't something 'official' out there.

[oldjapanesebikes]

Well - this service bulletin was 'slipped under my door' by a fellow who wishes to remain anonymous but to whom I have said a big 'thank you' from all of us interested in this topic ! It actually is #26 of a service bulletin series I haven't seen previously and answers my questions on the early Cobra carburettors - hopefully the others in the same series will also surface eventually ! I will also have this on the T/GT Resources web site in a few weeks.

Enjoy !

[oldjapanesebikes]

Does anyone have a good photo of an original Cobra shift lever ? Thx !

[argo1974]

Ian, special thanks to you and to your fellow for that service sheet.

The correct lever looks this: http://www.bilder-hochladen.net/files/b ... x-1aa4.jpg" onclick="window.open(this.href);return false;
The hexagonal bolt was already replaced with allen head one due to sloppy shift lever. And, the lever itself is bent outwards.
In case you need better pics I can take the lever off the bike and post photos at the weekend.

The lever is little different from later style T500 one as do other parts like brake lever or chain cover.
Argo

[oldjapanesebikes]

In case you need better pics I can take the lever off the bike and post photos at the weekend. The lever is little different from later style T500 one as do other parts like brake lever or chain cover.

Thanks Argo - that would be appreciated. What I'm wondering is whether the shift lever I have has been modified. I've attached a couple of photos below. In the one immediately below, a new style lever is on the left and the one that came on the bike is on the right - note that the underside of the one from the Cobra has been cut all the way through. Did someone do this, or is this how they came ?



This one shows the new style on the left again, and the Cobra one on the right - the new style doesn't fit the chain/sprocket cover as there isn't enough room for the lever boss to clear the cover casting when fitted to the shifter shaft spline. The chain cover I have is the one with no grease fitting.



I'm thinking of grinding down a later style lever to fit the older style side cover as it is a better, stronger design. Also - the one that was on the bike is a 6mm pinch bolt, and the later style is an 8mm one, again a bit stronger.

Also - made smoke on Sunday ! Lots still to do (including fixing that right mirror ), but it is coming along.

[argo1974]

Ian, I took few pics at the weekend but unfortunately forgot my camera.
The lever looks exactly like this one incl. rubber cover and cut on underside:
http://i223.photobucket.com/albums/dd59 ... 010013.jpg" onclick="window.open(this.href);return false;"
http://i223.photobucket.com/albums/dd59 ... 010014.jpg" onclick="window.open(this.href);return false;"

It already has 8mm bolt and kick shaft bore aligned off the center like on pics above. I can read Made In Japan #8 on it, whereas # looks similar to Chevy's bow tie logo.

Argo

[oldjapanesebikes]

Thanks - so mine has been butchered - I had a good spare in my stash, so I've swapped it out.