1977 cb750f2

[xcmandan]

Does anyone know if the lower engine cases are compatible with each other. I have an 77 750f2 with a cracked and poorly welded lower. I'm in need of another lower case. What years and models are compatible???

 

[dirtdigger]

You have to replace cases as sets...upper and lower are machined as pairs. You need to stick with a 77 or 78 f2 case.

 

[xcmandan]

You have to replace cases as sets...upper and lower are machined as pairs. You need to stick with a 77 or 78 f2 case.

Ok, Thanks Dirtdigger. So now I have to start searching for a lower case. You wouldn't know anyone that has one, would you??? Hahahhaa

 

[dirtdigger]

You will have to look for a set of cases, cant use just lower, you need both the upper and lower. Watch ebay, the 77 and 78 f is harder to find they are much rarer then the K. You may be able to use 77 and 78 K cases but I cant say for 100%. The biggest thing with the f motors is the output shaft and sprocket stick out farther from the block for the wider stock rear tire on these models. The cases are also wider at this point to support the longer output shaft. You would be best to stay with the 77 and 78 f block so you know it will fit. I do have a set but not really looking to sell. If you cant find a set hit me up later and we can talk about them, cant guarantee I will sell though.

 

[xcmandan]

You will have to look for a set of cases, cant use just lower, you need both the upper and lower. Watch ebay, the 77 and 78 f is harder to find they are much rarer then the K. You may be able to use 77 and 78 K cases but I cant say for 100%. The biggest thing with the f motors is the output shaft and sprocket stick out farther from the block for the wider stock rear tire on these models. The cases are also wider at this point to support the longer output shaft. You would be best to stay with the 77 and 78 f block so you know it will fit. I do have a set but not really looking to sell. If you cant find a set hit me up later and we can talk about them, cant guarantee I will sell though.

Thanks. Yes I have done research on that. I am looking for top and bottom cases for a match. Both are cracked. Mid January 2018 will be 1 year of searching. I'm losing my mind over this. It is my first build. I'm 44 years old and would really like to complete this. But if I have to unload the bike. I guess I'm alright with it. Just really bummed out. I don't have a lot of $$ to buy cases. I'm looking at $150 tops. Sorry for a low number but that's realistically what I can spend.

 

[amc49]

The cases are indeed machined in matched pairs, mismatched and the bearing bores are likely out of round and instant problems that.

 

[dirtdigger]

Keep watching ebay...I'll check a couple of people see if I can round up a set for you.

 

[dirtdigger]

Put a wanted post in the classified section here also. Never know someone might speak up and have a set.

 

[xcmandan]

Keep watching ebay...I'll check a couple of people see if I can round up a set for you.

Thank you so much. You guys are great.

 

[xcmandan]

Put a wanted post in the classified section here also. Never know someone might speak up and have a set.

Thanks so much!!!!!