Clutch leaks

[Germanrazor]

I have fluid leaking slowly and what I mean by that is a drop here and there when the bike sits for some time without being ridden. Not normal I know but weird it slows to ceases if ridden. I need to take it to the local Honda dealer to see about the leak as I suspect it is clutch related as the reservoir for it does go down slightly over time.

Anyone else had this issue and where was it isolated to? I have a 2005 model with 31k on the odometer.

 

[Nashcat]

I would suspect the clutch slave cylinder. Wait for more advise from this group, before taking it to a dealer. The dealer won’t have a clue how to fix it, and the mechanics have probably never seen the slave cylinder on an ST1300.

John

 

[SupraSabre]

A stealership will probably tell you that the engine needs to be pulled to replace the Clutch Slave Cylinder.

It's not necessary. There is a thread here that shows you how to do it.

Article on how to replace the Clutch Slave

I have replaced a couple of them. And I go beyond what is in the article (which I included in it)

Good luck if you decide to try it!

 

[Esti1300]

I would suspect the clutch slave cylinder. Wait for more advise from this group, before taking it to a dealer. The dealer won’t have a clue how to fix it, and the mechanics have probably never seen the slave cylinder on an ST1300.

John

+1 on this being the culprit

 

[SMSW]

@Nashcat was absolutely right about the dealers not being able to service these bikes. STs tend to be very reliable, comparatively few were made and as a result, few mechanics have worked on them. The number of stories about dealers who screwed up routine service on this bike is incredible. IIRC, the flat rate manual says the slave cylinder replacement takes 8 hours - remove the engine, swap the slave, replace the engine. One of our members, a self proclaimed novice, swapped his clutch slave cyl in 4 hours. It will for sure take a few whispered incantations, and maybe a few pejorative utterances, but it is doable. We even have a couple of members who will talk you through the procedure. Hover your cursor over the blue screen name: @Igofar and click on start conversation. This is the private message (aka email) function. Tell Larry your problem and give him your phone number and a time to call you. Be prepared to take notes.

 

[Kevcules]

Check out MaxPetes very well detailed and helpful "how to" in the articles section, or click on the link provided by SupraSabre

 

[MaxPete]

It sounds like you've got a bad clutch slave cylinder or CSC. Many 15-20-year-old ST1300s have this problem.

The repair is pretty inexpensive - perhaps $75-150 or so for the parts and I wouldn't bother trying rebuild your old CSC - it isn't worth the trouble. The task is also easy - but I urge you to read the article on this topic as there are some tips and tricks.

No special equipment is needed - just some small wrenches and sockets and a little jar of Vaseline (the stuff you put on a baby's bum to stop chaffing and redness).

Pete

 

[Esti1300]

No special equipment is needed - just some small wrenches and sockets and a little jar of Vaseline

And maybe a good dose of patience as the repair area is tight. Lots of useful advice and tricks (Vasoline) using the articles posted in this thread to help make your CSC repair experience quick and painless

 

[oilspot]

I'm sometimes a nervous nelly when things get a bit off kilter on my ST. I've had it for almost a year now and flushed the clutch system twice, still the fluid gets dark pretty quickly. Then I started smelling a very unique melting plastic smell and I notice my clutch fluid was a tad low. I quickly ordered a new CSC and gasket...

The replacement took me about 2.5 hours at my usual slow and steady pace. I had it on the side stand most of the time (lacking a motorcycle jack). At least 1/2 hour of that was spent on bleeding the system after installation. Hardest part for me was removing the old gasket. Everything else seemed to go smoothly. Larry talked me through an extra bleed step at the MC and things seem nice and smooth. The source of the smell was a rubber channel laying on the exhaust that I couldn't see till the Tupperware was removed - LOL. I still think it was good to replace the CSC as you can see in the pictures below.

The ugliest part wasn't really from leaky brake fluid. It appears to be a bit of sludge from the oily pushrod and some water intrusion past the gasket that mineralized over time. I pulled apart the CSC and could see evidence of wear and some corrosion from water in the fluid. The new one does seem more smooth, but then my bike goes faster when I polish it too FWIW & YMMV.

 

[Mr.E]

It's debatable if the CSC gasket needs replacing - it's not actually sealing anything!
Next time I do this job I'll just put a smear of high temp grease over the mating surfaces.

 

[oilspot]

It's debatable if the CSC gasket needs replacing - it's not actually sealing anything!
Next time I do this job I'll just put a smear of high temp grease over the mating surfaces.

Perhaps…. My interpretation and observation is that the gasket protects against moisture intrusion into that space. Most of the smutz on the face of the piston appears to be from something that leaked into the space and very little of that is from brake fluid.

 

[ST1100Y]

It's debatable if the CSC gasket needs replacing - it's not actually sealing anything!
Next time I do this job I'll just put a smear of high temp grease over the mating surfaces.

I'd say it keeps road spray and washing water out the cavity, compensates thermal expansion/contraction between the casings and possible prevents corrosion-welding...

 

[Mr.E]

You would think that is the case to protect the CSC internals - but - if you look closely, there's a hole in the rear casing near the bottom that lets junk into that piston/push rod working area, as well as letting any leakage out.

 

[oilspot]

You would think that is the case to protect the CSC internals - but - if you look closely, there's a hole in the rear casing near the bottom that lets junk into that piston/push rod working area, as well as letting any leakage out.

Yup, indeed there is a weep hole at the bottom. My gasket appeared to leak on the top (or close to the top). I'm not sure exactly what the crystalized material was, looked like mineral salts from evaporated water buy no chemical analysis was completed. It's an odd location to spray with a garden hose, but I'm sure road spray from the rear tire could impinge on this area to some degree. Regardless of the purpose, I replaced the gasket just like the Honda gods advised and went about my day.

 

[Igofar]

A couple pictures of the weep hole...
And, how to remove the oil seal if replacement is needed.