Topic: 750f differences I have found out 75-76/77-78

[78 k550]

Hey All,
 I'm swapping a 77 750F to a 76 750F and noticed a few changes they made. It doesn't seem they had the extented rear fender on the 76 but do on the 77. The rear part of the frames are different where the swing arm mounts and rear foot pegs. The way the rear disc cylinder mounts up to the frame and aluminum brace. I tried putting the 77 rear mag on the 76 and found out the swing arm's are of different size. So I had to swap the  77 swing arm over to the 76 to fit the comstar. The 77 is about a 1/4" wider. Now that I'm using a 77 rear caliper with a 76 resivor I might need to have a rear brake line made. The bottom of the tripple tree's are different. The 76 has a bracket that mounts to the bottom of the gauges and inserts into the bottom triple tree's with some rubber groumets for vibration. There is also a straight tube across  for the blinkers on the 76 style. The 77 use fork ears for mounting the headlight and blinkers. on the 76 they use a single disc up front and a dual on the 77. So where the horn and proportioning valve mounts on the bottom of the triple tree are different and had to swap them.The 76 battery box mounts with 4 bolts and the 77 is 3 in a tri-angle shape, so it not a direct swap. I think thats about it for now I'll post up some progress pics and if I find any more things out. If I'm reffering to a 76 i'm meaning 75-76, if reffering to a 77 also both 77-78 years. I hope this is usefull to someone else and all that needed to be swapped over. Have fun all I hope to be riding this in a couple weeks.

Paul

[Slim_SLC]

paul, did you find any other obvious differences?  do you happen to have pics of the tanks/seats/ducktails side by side that you could post or email me?  I have a 75F, but I suspect that it has a 77 tank, seat, and ducktail on it. 

thanks!

[KB02]

The carbs are different, too, arn't they?

[Orcinus]

Yes, the 77-78 had different carbs than any of the other 750's.  They also have a different sidecover on the left side.

[Clyde]

Slim_SLC,
I have a F1 with a F2 tank on the bike.
The differences are in the petcock, the F1 has a 19mm thread and the F2 has a 16mm thread. There are also the cosmetic differences such as the paint scheme and badges (the badges use the same mounting points and distance, and hence are interchangeable))
The ducktail on the F2 had a badge on the back(two holes) and uses three of the retaining bolts/clips per side (rather than two of the F/F1) to hold the seat trim on. I had an F2 ducktail but managed to find a better F1 example before painting. It would not have worried me as with the badge holes filled, it looks the same and the extra mounting for the trim is better.

Regds Clyde

[scout18]

seems to me taht the 77-78 left side covers are the hardest to find I am looking for one by the way so if you have  one  or know of one I am very intrested in it.

[Orcinus]

David Silver Spares has both sidecovers for the F2/F3.  I think they're the only ones that have one.  There used to be a Fiberglass shop in Australia that sold one, but the last time I checked they no longer list it.  The only other good suggestion I've heard is to patch up a old busted one and use it to mold a new one from fiberglass.  Even if you can find a NOS one, the plastic that Honda used appears to get brittle with age.  I would doubt that it would last very long, certainly not for what you'd end up paying for it.