Honda ST70 Gear Shift Problem

Quinton

New Member
I am restoring a Honda ST70 - not sure of exact date but somewhere around 1972 I guess - S/N ST70-561867.

Looking for advice on how to fix a gear shifting issue. I had it running but it had no power and would not shift into third gear. Have opened the engine up to replace gaskets and rings and inspect the gears. See video attached which shows the shifting.

One can see it shifts quite easily but stops just short of hitting the last spot. Any advice on what to do next would be great.
 
Spin the countershaft when shifting. They do not like to bench shift. If you had issues when the bike was running, it's time to split the cases and inspect the shift forks. Notice the currently listed 'ebay' fork on the right has the telltale 'smiley face' at 9 0 clock, it's garbage. If one is bad replace BOTH and new fork pins!
 

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Thanks for the info - it shifts into the last gear fairly smoothly now when spinning the countershaft as suggested. I can feel it spins a bit stiffer in that last position.

Considering it did not shift when running would you still recommend splitting the case? I have not done this all before - learning as I go.
 
Did you find any problems that you can blame the shifting problem on? Loose, missing, or worn parts? It LOOKS like it's shifting nicely in the video.
How many miles are on the engine?
 
What state do you live in? Lots of members here, maybe someone is close by. I would split the cases and inspect the forks and clean out all the crap in the cases and put in a new CHP clutch if you do not want to rebuild the original clutch. They are cheap. The biggest hurdle is getting the 3 clutch face cover screws out clean. There is a special clutch nut tool you will need once the cover is off. If they get stripped you have to carefully drill em out, if buying a new clutch, you don't have to worry so much.
 

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Did you find any problems that you can blame the shifting problem on? Loose, missing, or worn parts? It LOOKS like it's shifting nicely in the video.
How many miles are on the engine?

Everything looks good on the shifting mechanisms, nothing visibly loose or worn and it's shifting nicely using the toe shifter. Guess I've come this far, can't harm opening it up further and cleaning it all out.

 
What state do you live in? Lots of members here, maybe someone is close by. I would split the cases and inspect the forks and clean out all the crap in the cases and put in a new CHP clutch if you do not want to rebuild the original clutch. They are cheap. The biggest hurdle is getting the 3 clutch face cover screws out clean. There is a special clutch nut tool you will need once the cover is off. If they get stripped you have to carefully drill em out, if buying a new clutch, you don't have to worry so much.
I'm in Cape Town, South Africa - parts are difficult to find locally but I have family in the US who are visiting soon. Opening it up and cleaning it out sounds like the right thing to do. Will check back in.
 
The rest of the bike is in good condition. Have redone the rims and sprockets and got some parts from MyTrailBuddy. Also had the top end vapour blasted and ready for new rings.
 

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The rest of the bike is in good condition. Have redone the rims and sprockets and got some parts from MyTrailBuddy. Also had the top end vapour blasted and ready for new rings.
I like that green Dax ST70 frame in the back ground...Hope that is next on the list to fix up...
 
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