Review: Triumph 650 Twins Camshaft Bushing Line Reamer Tool Kit

Review: Triumph 650 Twins Camshaft Bushing Line Reamer Tool Kit

Triumph 650 Camshaft Bushing Line Reamer Tool Kit


Over time, just like everything else, your Triumph's camshaft bushings will wear out to the point that they will need to be replaced. Although changing the camshaft bushings can be done, it can also be a really time consuming job. If your camshaft bushings do not appear to have excessive wear, we recommend leaving them. Changing the camshafts bushings requires the proper tools, time, and also knowledge. This blog post is not about how to change and install Triumph camshaft bushings, instead its to show you this amazing tool that we stock to help you achieve that perfect spinning and aligned camshaft.



Triumph Camshaft Line Reamer Tool Image

 Triumph camshaft reamer tool kit with 7/8" ball, 13/16" chucking reamer and pilot sleeve.


So you just installed a set of 4 sintered bronze camshaft bushings in your vintage Triumph twin. You try to install your camshafts but realize that both the timing side and drive side bushings are to tight to insert you cam. So what do you do now? Before you start cursing at your Triumph. ... keep in mind that your bushings must be line-reamed before you insert your cams inside the bushings. When the camshaft bushings are inserted into the case, the inner diameter of the bushing will slightly crush causing the bore to close. When this happens you will need the correct tools to bore each camshaft hole to the proper size. Our line reaming tool set comes with 3 items. A 7/8" chrome ball bearing, 13/16" chucking reamer, and a pilot sleeve as pictured above. Please note that this tool set is only compatible with sintered bronze bushings. If you are planning to install the solid brass bushings that we stock or Kibblewhite bushings, then this tool set will not work.



Line Reaming Camshaft Bushings On 1968 Triumph 650

 Line reaming the drive side camshaft bushings on a 1968 Triumph TR6R 650 using our high quality tool kit.


First, the 7/8" chrome ball bearing is designed to broach the timing side bushing after the bushing has been installed in the case. Sintered bronze is a very soft material that should be either broached or reamed. With the ball bearing having an O.D. 7/8" (0.875"), your cam shaft journal should be approx giving you approx .0015"-.002" clearance once the camshaft is installed in the timing side bushing.



Triumph Workshop Manual Image Camshaft Reamer

 Original camshaft bushing reaming tool as pictured from a Triumph 650 workshop manual. Originals are very hard to find.


Once the two timing side bushings have been broached using the 7/8" ball bearing, you will have to use the 13/16" chucking reamer to line ream the two drive side bushings. In my opinion, this is the most important part of the process. If this step is not done properly, you bushings will bind. The 13/16" chucking reamer is guided by an alloy pilot that slips into the timing side bushing after it has been broached by the 7/8" ball bearing. Once the engine case bolts have been fastened (tight), you can go ahead and start cutting the bushings. This same tool kit is very similar to the types that Triumph use to offer back in day. If done correctly, it works. This is the most accurate way to get your camshaft bushings aligned properly, in fact, there are some online retailers offering pre-reamed camshaft bushings, but to be honest there is no such way. Purchase your new Triumph 650 camshaft bushing reamer today. Stock is indeed limited.


The Triumph camshaft reamer kit that we offer for sale will work with most Triumph 350, 500, & 650 Pre-Unit twins, and will also wok with Triumph 650 & 750 unit twins from 1963-1982. Keep in mind that this should only be used with sintered bronze bushings only.


 Reamer Tool                                  Ball Bearing O.D.                       Material 

13/16" HSS Chucking Reamer       7/8" Chrome Bearing             Alloy Sleeve


  • Larry Mumford

    Will this reamer work on phosphor bronze bushings? Thanks!

  • donald a molnar

    hi i just ordered your reamer kit and forgot to use bfcmsale 10% off please apply to price. thanks donald molnar, dons racing engs.

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