July 10, 2017

Service Bulletin: Clutch Release Rod 57-1736

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Today's Triumph service bulletin is in reference to Triumph twins suffering from premature clutch push rod wear and failure.

This Triumph service bulletin is dated May 8th, 1970 - and was released to all Triumph dealers at that time. I will go into further detail below of what to look for in a worn clutch push rod and how to replace it.

The information that I will be discussing today can also be applied to BSA singles and twins along with different marks of Triumph motorcycles. If your vintage British motorcycle features a clutch push rod then I recommend that you keep reading as this post is relevant to you.

What is a clutch push rod?

A clutch push rod is a narrow rod that is located inside the mainshaft. Inside the mainshaft the clutch rod is allowed to pivot left to right. When you pull the clutch lever in on your handlebar an actuator engages the clutch push rod (timing side end) and forces it towards the basket which allows the clutch to disengage when it makes contact with the adjuster screw. The adjuster screw is normally found on the outer clutch pressure plate.

In essence the clutch pushrod is the leading factor of when your clutch will engage and disengage. Without the clutch pushrod you will not be able to properly operate your clutch and transmission

How does a clutch push rod wear?

When you pull in the clutch lever you have to keep in mind that the clutch push rod is under a tremendous amount of stress. When the clutch is disengaged (with the lever pulled in) it is putting pressure on both ends of the rod. This is typically where the damage and wear takes place.

I have also found that some new clutch pushrods that other sellers are offering are not properly heat treated on both ends of the rod. It is vital that when you replace your clutch pushrod or you make your own that you heat treat both ends to ensure maximum longevity.

Symptoms of a worn clutch push rod

Below are a few signs of a worn clutch push rod. I recommend that you check your clutch push rod to ensure that it is in good working. Replace when necessary.

•Constant adjustment

•Mushroomed ends

•Length not the correct size

Specifications chart

Here are the full specifications on the Triumph T1736 or 57-1736 clutch push rod. I also included the specs on the BSA unit twins clutch push rod.

Brand	Part Number	O.D. (Outer Diameter)	Length	Finish
Triumph 1963-1982	57-1736 (T1736)	.219"	11 13/16"	Heat-treated ends
BSA 1962-1972	68-3229	.219"	11 1/8"	Heat-treated ends

How to change the clutch push rod

Shown is the clutch adjuster screw and nut on a Triumph 650

Changing the clutch push rod is a very simple process. Most Triumph models have an inspection cap on the primary cover which you can remove. Once the inspection cap is removed you can remove the clutch adjuster screw and locking nut. Once removed you can pull the clutch pushrod out.

Those that do not have an inspection cap on the primary cover you will have to remove the entire primary cover. Once the primary cover is removed you will now be able to remove the clutch push rod.

Installing a new rod take minutes. You do not have to remove any other parts or touch your clutch lever unless the timing side end of the rod is mushroomed as described in this service bulletin. In some rare cases you would then have to remove the timing cover and pull the clutch rod out from that side. Once done replace or inspect your clutch rod, set your adjuster and secure your lock nut.

"Thanks for reading..."

If you follow the steps as described above and in this service bulletin you will be able check your clutch push rod and also eliminate any future damage. If you have any further questions please let us know by commenting in the fields below. Check out some of our other blog posts similar to this one. Thanks for reading!

7 comments

Herve Caboche June 16, 2021

Thanks a lot for all the details, very clear explanations.
Herve Caboche June 16, 2021

Thanks a lot for all the details, very clear explanations.
Arshad July 03, 2020

Please let me know the material of the push rod, the specs of that material.
Classic British Spares July 14, 2017

@Darrell – that is exactly what factory should of done! Well done :) Thanks for reading and commenting today.
Darrell ufland July 13, 2017

As I own a 1969 triumph twin been down that path before many times. Until one day many years ago, I could not get a clutch rod from the local bike shop. So I made my own. Being a mechanic and a machinist, was not too hard. The good thing is the one I made is still in my bike 30 years later. Took a standard rod and braised a ball bearing on each end. Polished it and presto, never wear again.

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