What a day - throw away your 9 mm taps

[davexz]

I spent all day working on my starter clutch.  Last night I had it all put together on the fly wheel with the bolts pounded over to make sure they didn't come out.  The flywheel has two 8 mm bolt patterns - one for the clutch and one for a flywheel puller (3 bolts in each pattern).  Well, since my clutch bolts had come out and rounded out the threads (the previous owner who must not have heard any wierd sounds), I decided to use the other good pattern of threads and re tap the rounded out ones bigger and use that pattern for the flywheel puller.  Sounded like a good idea and it was but - JUST DON'T USE A 9 MM TAP because bolts are near impossible to find.  After looking on line for 9 mm bolts without any luck, I didn't want to go forward and have troubles down the road when I would want to take the flywheel off (or someone else wanting to take it off) so I tore it all down and tapped them out using a 10mm X 1.25 tap.  Stupid me - I thought one size up would do it and didn't appreciate the scarceness of 9 mm bolts.  Why are 9 mm taps so easy to find? Kinda like the wrenches - I keep threatening to throw away my 9, 11, and 16 mm wreches because I never use them but always pick them up.  ;)

[Raj1988]

dang i that never even struck me... i've NEVER used my 9 and 11 mm spanners!! They are as all dusty hangin on the garage wall

[Hartless]

really. are you guys talking about just using 9 and 11mm for the vision?or in general? because when i use them quite often. especially when i had my ford ranger.....

[Raj1988]

Dude, i barely wrench on anything else... on the car, i'll go as far a changing rotors and pads and sparkplugs!!!

Not confident enough to go screw around with anything else...

[davexz]

I am talking about on anything, but I don't work as much on cars as motocycles so maybe you need them more there.

[Tiger]

 :) Be aware...You will find, on Japanese manufactured vehicles/equipment, JIS nuts 'n bolts!!! The threaded fastener will be the correct 'normal' size, however, the hex head on the bolt (or the nut) will be a smaller size compared to 'normal' metric nuts 'n bolts.

         8) .......TIGER.......  8)

[Rikugun]

If I threw out my 9mm tap I'd be guaranteed to need it next week.  :(    :'(

Tiger, more info please!  Isn't JIS the "normal" standard making the OEM bike hardware "non-standard"? And why 2 standards?

[fret not]

JIS stands for Japanese Industrial Standard, they also use ISO on some bolts and nuts. ISO are indicated with a small dimple like a center punch makes and are usually the smaller sizes like 5mm thread and smaller.  JIS stuff comes standard on Japanese made machines as opposed to the European alternative.  Some parts are interchangeable but many are not.

[Lucky]

among the minutia of Vision Crap in my head is this tidbit:

there are 2 different flywheels on these bikes. 

one has the puller & clutch mount bolts @ the ssme circumfrence. (6 holes equal distance from the center)

the other has them at different distances.

if you have the first you can retap the holes the holes the clutch was first mounted to larger & use for the puller next time.

if you have the second type you'll have to ditch the flywheel or helicoil it.

[fret not]

Lucky, you didn't really mean that did you? :D

If you need the threads repaired in the flywheel it would be better to weld them up and re do them properly with nothing that could possibly work loose, especially like a Helicoil.  It would be cheaper to find another flywheel I think.

[Lucky]

you'd be surprised how strong properly installed helicoils are. when you use a helicoil type set up you are basicly increasing the bolt size which relates to an increase in holding power.
the helicoils are made of harder materials than the relativly soft metal of the flywheel. if i remember right they are a stainless steel alloy.

properly installed helicoils don't work loose.  your streching the threads, same as a fastener

if you really want to go crazy from there you could back it up with a graded nut, although i'm not sure there is room for it.

there are other brands that have even better reviews, also, helicoils are used to hold the Space shuttles fuel tanks on.  i thought that was worth a mention...

[Rikugun]

I have a question about the starter clutch bolts.

Assuming you've done the mod involving longer screws that have been peened over to prevent them from backing off -

1. Is there any danger of impact/vibration damage to the rotor magnets when hammering away at the screws. Or for that matter, when using BFH blows on the puller to facilitate removal?  and

2. Once peened over, has anyone had the need to later remove the starter clutch? What heroics are required to remove the now peened over screws?

[Lucky]

1. Is there any danger of impact/vibration damage to the rotor magnets when hammering away at the screws. Or for that matter, when using BFH blows on the puller to facilitate removal?

Doesn't seem to be.  no one has ever reported any problems.

Once peened over, has anyone had the need to later remove the starter clutch? What heroics are required to remove the now peened over screws?

two choices: either grind then peened ends out with a Dremil or similar tool, or drill the small end out a bit.

The repair should be permanant though

[Rikugun]

The repair should be permanent though

Agreed, should be. However, I'm talking about the exceptions in life! Say the rollers or springs get to the point of clutch slippage and need to be addressed. Or the magnet cracked or shattered in a crash and you need the clutch to install on your spare clutch-less flywheel.

Since grinding would be needed for removal anyway, I wonder if small spot welds would be a quicker method to safety the screws. Has anyone ever considered or tried this method?

[Re-Vision]

A piece of soft iron can be magnetized or demagnetized with physical shock (Hammer blows) rather easily, the harder magnetic alloy materials or much harder to demagnetize. Obviously the blows from flywheel removal or not making enough change in the voltage output to cause a problem in its regulation. I thought that was a really good question gary.    BDC