Originally Posted by TipsyMcStagger
I am completely airhead illiterate, so please excuse my ignorance; but why exactly does the 1974 have a negative reputation?
I'm considering having a look at a rough 1974 R60/6 for a Cafe project. It's my understanding that '74 was the final year of kickstart, which is appealing to me.
1974 is the first year of the 5 speed transmission. The /5 four speed was the final refinement of the older /2 trans, they are very similar, some of the parts interchange. But the industry was moving toward 5 gears instead of 4 so the Getrag 5 speed.
I think there were two problems basically.
One was the grooves that the shifter forks ride in had edges that were too thin and these gears could break. I think we had one on Adventure Rider that was broken just with in the last couple of months. I'm not sure it was all of the grooves, it might have been two of the three I think or it might have been all three but they do break and the trans can lock up too I think when this happens. In order to make the edges of these grooves strong enough in 1975 the shifter forks were made thinner for thinner grooves and the edges then grew thicker. So different gears, at least three gears, and different forks.
The kick starter never had enough throw to it. It was difficult to start the bike with the kick starter unless it was in top notch tune. One of the parts used on the kick starter was not hardened properly or somehow made not properly. I think it was a hardness problem. The part that is at fault is apparently the gear on the input shaft that the segment gear turns (I forget what it's called). The electric starter had been proving very dependable and had increased in size so that this was determined to be all that was really needed to start the bike. A substitute hardened gear was made available for awhile but it is NLA anymore I think. If you wore the part out by using the kick starter the lever hung down half way when not in use and you hit your leg on it.
I don't know if there are any other items we call "problems" but I think there were some other changes.
I wasn't into Airhead bikes when all this was going on but I have tried to piece the story together from small snippets of information that pop up now and again. I don't know if I have all of the story right yet so I'll keep my ears open for more info.
The bottom line is that I don't recommend you try to even save a 1974 transmission. If you get one that works count your lucky stars. If you really have to have this particular trannie get one of the Gurus to rebuild it and be prepared to spend accordingly. The later GS and G/S bike had a kick starter that could be special ordered. I think this is the same design with better parts. These trannies bring a lot more when auctioned than most 1974 trannies.
If you have a '74 bike that you want a kick starter on for show purposes then consider a dummy starter that has the lever but is not complete. If you do have a working kick starter I suggest you don't use it because it may break.
I once had a 1974 R90/6. It was hand painted with a brush and had a tractor battery that died on me. The kick starter never worked and I had to push start that bike. But I was younger then.