1961 CB72 Project

[G-Man]

Steady on there Dave..... :-)

A while back I 'realised' that I was rushing things to get bikes together and just re-focussed on enjoying the 'journey'. Now I just use this as a change from my working life that involves travel and sitting alone at night in hotels around the world.

I am interested in the Engineering that went into the bikes and why things changed from time-to-time. I like to find out the 'why' by measuring and testing, if I can.

G

I have been away from this forum for a few years and on revisiting I found your thread. I have read every post and am just amazed at your dedication and detail. It makes my restoration efforts seem like those of a cave man. I await further installments with anticipation.

Dave in Oz.

[G-Man]

Not strictly 1961 CB72 but I thought I'd get these tensioners finished beforte I move on with the project. I found the 8 wheels that I hadn't put bearings in and did that then set about assembling the remainder of my pile of parts.

As I worked through I discovered stripped threads in three of them so diverted back to some quick heli-coil repairs. These kits are now a fraction of what they used to cost so I have kits in most sizes.

These are regular M6x1 so nothing special. The re-coil kit I had to hand is much simpler than the original Helicoil system but still uses the same wie coil. You get a drill and a tap to make the thread for the insert and tools to insert the coil and then break off teh driving tang.



The hole is drilled oversize and tapped and that is all that is needed to prepare for the insert.



The driver tool just has a slot to engage with the tang on the insert and just winds it in. You can get inserts in different lengths but I just settled here for the regular 1.5 D inserts (length is 1.5 x diameter).



I like to insert the coil just below the surface so that it doesn't catch on the bolt head and get dragged out.



Three tensioners got the treatment in less than 1/2 hour and that seemed like a good investment to get three more parts added to my inventory.



Time to get on with some real progress on the project.


G

[Steverino]

Very interesting G. Do you have a part number on that kit? I've got a few CB160 Heads with stripped spark plug holes.
Steve

[LOUD MOUSE]

I don't recommend that sort of coil for spark plug threads.
I use TIME CERTS (spl) to repair my damaged plug threads. ............lm

Very interesting G. Do you have a part number on that kit? I've got a few CB160 Heads with stripped spark plug holes.
Steve

[G-Man]

Steve

I just googled LM's Time Sert and they look pretty good for spark plug holes as you can peen the end over to stop it winding out. The little flange on the top stops it winding in. Quite neat.

http://www.timesert.com

If you want helicoils for anything else just do a search on eBay for thread repair coils or heli-coil.

G

I don't recommend that sort of coil for spark plug threads.
I use TIME CERTS (spl) to repair my damaged plug threads. ............lm

Very interesting G. Do you have a part number on that kit? I've got a few CB160 Heads with stripped spark plug holes.
Steve

[LOUD MOUSE]

I thank you for your response. .
I have now purchased all sizes of the metric Time Sert and recommend them to all others.
Once a person has used them Heli Coil is OK but not up to par with the Time Sert.
Install same as Heli Coil as for installation time.
They don't require you to peen the end over.
Same as any new thread kit the cost isn't cheap to start however the coil/threads will STAY in place. ..................lm

Steve

I just googled LM's Time Sert and they look pretty good for spark plug holes as you can peen the end over to stop it winding out. The little flange on the top stops it winding in. Quite neat.

http://www.timesert.com

If you want helicoils for anything else just do a search on eBay for thread repair coils or heli-coil.

G

I don't recommend that sort of coil for spark plug threads.
I use TIME CERTS (spl) to repair my damaged plug threads. ............lm

Very interesting G. Do you have a part number on that kit? I've got a few CB160 Heads with stripped spark plug holes.
Steve

[G-Man]

Before I move back to my project 'proper' it was time to do a quick inventory. .... :-)



Id forgotten that one of the castings had a crack and will need fixing but I think I have enough to be going on with....




Off on my travels tomorrow but Hope to be back for more fettling at the weekend.


G