Don;
I have made the change over to full synchro trans in a number of constant transmission Honda 600 using the early case. The lower case is almost the same, but in order to have the full synchro counter shaft to fit, the center fin (rear section) must be cut. Or the shaft will not fit.
Bill
Re: [2cylinderhondas] Re: Synchro conversion
Re: [2cylinderhondas] Re: Synchro conversion
The shafts are the same length, yes. However the dimensions are different in that the lash configuration is different on the full synchro trans from the Constant.
The bearing keepers are the same but there is much more wear on the large bearing keeper where the oil pump rod thrust bearing rides against it. If you are using used transmission internals then remove the large bearing keeper from the reverse gear side and use it on the oil pump side. The thrust washers are the same on both transmissions which is good if there is some lash issues. They are all brass so sanding them down to remove grooves is easy and if you need to add one to make things tight, sanding them smaller to make them fit is easy to do. See chapter 6 in the Coupe supplement shop manual for more information on how tight they are supposed to be.
Bill
The bearing keepers are the same but there is much more wear on the large bearing keeper where the oil pump rod thrust bearing rides against it. If you are using used transmission internals then remove the large bearing keeper from the reverse gear side and use it on the oil pump side. The thrust washers are the same on both transmissions which is good if there is some lash issues. They are all brass so sanding them down to remove grooves is easy and if you need to add one to make things tight, sanding them smaller to make them fit is easy to do. See chapter 6 in the Coupe supplement shop manual for more information on how tight they are supposed to be.
Bill