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New OEM clutch pack. Clutch not engaging

8 posts Started 17 Nov 2023 Last recovered post 21 Nov 2023 Wayback Machine snapshot 1 Dec 2023

#1

Installed new clutch on 2007 800a. Flushed clutch fluid.  Changed oil using Honda recommended type.  Motorcycle did well for ride around neighborhood which is about 2 miles.  Took bike out today.  Was not engaging after about half a mile.  Worsening until there was no engaging at about two miles.  Friction point was moving farther and farther on the lever. 

The correct clutch pack was installed using a manual.  New pressure plate springs.  All bolts torqued to spec.  Clutch area inspected and nothing unusual found.  

Clutch lever is snappy.  Pressure plate springs are pushing back.  

Thoughts? 

#2

Those are the symptoms of a blockage in the master cylinder I think. The small relief port gets blocked, and that prevents pressure releasing from the line. As you work the clutch and/or the fluid heats, the line pressure increases and starts holding the plates apart.

#3

Like a check valve.. That makes sense.  I was thinking the pressure plate is acting like it's being held away from the disks.  

#4

The master/slave on the clutch can be tricky to bleed properly. When I rebuilt both on my 6th gen it seemed as if the typical master to slave bleed had gone well but I was getting poor disengagement with the plates. Finally resorted to a slave to master fluid push with a syringe and that dislodged whatever air pocket was trapped.

#5

No pressure being retained.   Opened bleed port on slave and little came out. Nothing found in master cylinder bleed port but I did not have a fine wire to probe.  I just poked with a small paper clip. Placed bike on center stand. In gear  rear wheel locks with clutch lever released and turns with resistance with lever squeezed.  

Started next day.  Outside temperature 54°.  Clutch engaged initially.  Checked again with engine warm about 170°.  Clutch lightly engage then wouldn't.  Clutch friction point way to far out on lever.  Almost at point where lever sits.  I know the clutch pack is correctly installed. 

#6
expvet, 11/18/2023 at 12:37 AM

The master/slave on the clutch can be tricky to bleed properly. When I rebuilt both on my 6th gen it seemed as if the typical master to slave bleed had gone well but I was getting poor disengagement with the plates. Finally resorted to a slave to master fluid push with a syringe and that dislodged whatever air pocket was trapped.

This would cause poor disengagement due to the air bubble.  My issue is the opposite.  Great disengagement no engaging.  

#7

Will rebuild master cylinder.  Only kits exist can not get new master cylinder.  Bike too old. So I will not be replacing the orifice but plan to blow it out. 

#8

Definitely should be no need to replace the master cylinder, and actually if the master piston is not leaking you probably don't need to replace any parts. Just a full disassembly and  thorough clean and inspection. In the floor of the master cyinder is a small metal plate that sits into the main intake port, when you pick that out you will see the tiny relief port below. The metal plate's function is to stop a jet of brake fluid exiting the master when the cap is off during bleeding. Make sure this port is clearly ejecting fluid as the lever is pulled. 

End of thread · 8 posts recovered Wayback Machine snapshot 1 Dec 2023