M10x1.25 Left Hand Tap!!

I have 2 engines for my project bike, the one that is in it and a spare. I wanted to do a compression test on the spare but I have run into a slight problem, the starter clutch assembly is damaged, so I have taken the one off the other engine.
When I went to fit it I could not get the bolt in and on further investigation I found out why, the person who took the old one off has damaged the threads in the end of the crankshaft that the bolt screws into, this would not normally be a problem as I have various taps etc but not an M10 x 1.25 fine pitch Left Hand Thread Tap. Can anyone help??

Sorry mate, my 10mm tap is the very coarse thread and right handed !

So is mine, that's the problem!!

Sorry not got one, Only £4 quid delivered on eBay but they're from China. So they'd take a fortnight to arrive and probably made of chocolate.
http://www.ebay.co.uk/itm/New-10mm-10-x-1-25-Metric-Left-Hand-Tap-M10-x-1-25mm-Pitch-/160868234027?pt=LH_DefaultDomain_3&hash=item25747e732b

Might you be able to loan one from a local engineering workshop ? .... if there are any friendly ones local to you .... or could you take the necessary art to them to tap the thread ? .... not as good as having your won - but might get you out of a hole !

An UK based supplier has them in - but they are around £35 inc VAT !!!!!!!!

See www.engineering-supplies.com/.../m10x1-25-left-hand-hss-metric

Hello Andrew,
I`ve used these people for reamers and taps E.T.C, They`ve never faild to impress,,, I did a quick check and they have a  M10 x 1.25 fine pitch Left Hand Thread Tap for £18 ,,,

http://www.tracytools.com/taps-and-dies/left-hand-thread-taps-dies?product_id=1323


Good luck mate and I hope this is of some help.

Thanks for the info. I managed to sort it, I used a small cone cutter to remove the first damaged thread and then tapered the end of a spare bolt I had with a file, I then used a fine triangular file to cut some grooves in the end of the bolt, then dipped it into some cutting compound and a slowly wound it in (in 1/4 a turn, out 1/8 turn, in a 1/2 etc.....), it took a bit of doing but it worked!!
The engine now turns over but has no compression so it looks like the head is going to come off for further investigation

Sounds like its going to be 'one step at a time' with your new project then ! - Hope it all works out OK

It does not help when the Haynes manual only give you half the info, like telling you to align the cam cogs with TDC on piston2 and showing you piston 1 cams!!, also saying the cam guides need to be installed in a specific order as they are numbered and then does not let you know what the order is. The garage door also fell off again tonight, so that looks like another £400 spent, not a good day so far :(

You deserve a medal mate ! .... I admire your perseverance

OldManYam wrote:

You deserve a medal mate ! .... I admire your perseverance

I've a feeling you'll get there Andrew

I have now got a copy of the Clymer manual, it is so much better. I will re-attempt the engine tonight. I found out why the engine has no compression, the rings were stuck in the grooves so I got them out with the aid of a heat gun, GT85 and a thin sheet of Stainless Steel. The pistons are in very good condition and the bores look good to, valves look good and tappet clearance's were ok.

I have emailed a company about a new Garage door, I fancy a Roller Door as it will give me more room.

Got to go to work now :(