Throttle linkages

Loki

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When my F1 super sport came to me it was a real basket case, the engine was loosely in the frame and the rest of it was in bits.
I have a query regarding the throttle linkage, I haven't yet got the throttle set up in position so am only manipulating the throttle by hand but feel that the twist grip would struggle to open the throttle as the spring is so strong. I have accumulated a couple of spare sets of carbs to refurb and now have 2 different throttle linkages, on both the lower end of the reurn spring mounts the same but the upper end on one is to a grooved pin and the other is to an arm on the linkage much nearer to the lower attatchment point and hence resulting in a much lighter throttle action, so which one is correct for my bike, I imagine that the grooved pin type would need a longer spring but so far all I can find is the one spring which is too short to work with that linkage.
Part number for my bike spring is 16036-392-004 but I have been unable to discover the length of this spring, 71 to 76 K's seem to use the same spring so a bit puzzled!

Loki
 
No eggspurt , but I think this is late s-l400.jpg and this an early model s-l1200.jpg .
 
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Many thanks that makes sense mine is a 1977 F1 so I have the late carbs. All I need now are the late springs as they are clearly longer. Any idea if the part number I have is correct for the longer springs?

Loki
 
The even earlier Keihin carbs (mine's a K6) are incredibly stiff when you try to move the throttle mechanism on the gantry by hand. So, I don't think that's a good test.

Honda seem to have had a fear of the throttle hanging, stiff springs and push/pull cables. There's probably a story behind that.
 
That was my thoughts as well but it seems to be just a little too belt and braces, a light compression spring in each carb might be better? Seem to remember Amal did that with only a single pull cable! The older carbs I've built up snap shut firmly without any sign of hanging open. I have 2 of the earlier throttle linkages which I can swap in just means taking my carbs off yet again :-(

Loki
 
The pic shows that it has a squared off design , unlike the earlier bullet style . Your part number is correct and when you search , it does show that type of spring . The pic shows that it is pulled really tight and none of the rings are touching , maybe it is meant to be tight as , like the sidestand spring , that was a bitch to fit on my bike . I know on my F2 the spring is that tight I have trouble moving the slides unless I use the throttle . Most times I lever the wheel with a screwdriver if the cables are not attatched
 
When I fitted my side stand I fitted the spring to the frame and stand then pulled it into place until I could get the bolt in! It was a bit of a mare but got there in the end.

Loki
 
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