Help!!!!!

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Hi all. I'm looking for a little localised help (east lothian) as i'm trying to replace valve guides & i'm no mechanic.
Help would be really appreciated.
Cheers.
 
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If at all unsure take the head to a engine rebuilders who knows what they are doing, a badly fitted guide can ruin a head. I have the tools to fit them and have used them but would only do it on one of my own heads, would hate to ruin someone elses.
 
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Similar to Kommando, I've done it myself but wouldn't like to F**k up somebody elses and don't have the time at the mo. I can reccommend an expert who isn't expensive and resides in North Perthshire. PM me for details. Hopefully see you both at Applecross in June for the Tay Valley bash? :lol:
 
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hi cheif,not a big job really,first you need an understanding wife or give her enough money to go shopping for a couple hours so you can get the head in her beloved oven for half hour(gas mark 5 should be enough) the n either use the special tools for removing and replacing guides or use a drift to tap them out,to fit new guides first establish that the ones you took out are std size(there are oversize guides available for worn guide bores) i put the new guides in the freezer overnight and with the combination of a hot head and frozen guides they tap in easily, you will know when they are fully in with the change of sound from your first tap
 
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after fitting new guides the valve seats will probably need recutting so unless you have your own seat cutting tools you will have to take the head to a machinist
 
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Thanks all for your responses & wise words. I think I'll send the head down to Norvil or Hemmings. I presume bronze guides are better than normal giudes? If so i'll be asking them to fit bronze.
Cheers
 
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I've also done it like Chris di and it worked fine. One thing that would concern me these days is that the parts actually used to fit years ago. Now there seem to be so many "just off a bit" spares people are reporting here. A slightly oversize guide can cause a crack, so my tempatation would be to measure the parts first. If you cannot do this perhaps a local machinest can help.
 
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I have a set of NuWay seat cutters so can recut seats easily and its fairly idiot proof to do so if you do your guides then I can recut the seats, the cutters are carbide and do an excellent cut and don't bother regrinding the seats after unless the valves are not new. Applecross in June sounds good. I'm down in Ayrshire.
 
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Thanks for that Kommando. Turns out theres a bloke that lives in the next village from me who mechanics on vintage race bikes. He is going to do the work for me.
Another question, I know theres a special spanner required for the rear head bolt, but do I need another special tool for the front middle nut/bolt?
 

L.A.B.

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chiefdeal said:
Another question, I know theres a special spanner required for the rear head bolt, but do I need another special tool for the front middle nut/bolt?

The head bolt should have a 1/4 Whitworth hexagon (or 5/16 BSF, as they are both 0.525") regardless of the thread diameter and thread type.

So you will need a slim socket or box spanner to reach the central head bolt. You could try a 14mm size (0.551") but it could be a little bit loose?
 
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Cheers LAB. I've checked the Norvil catalogue & noted that there is a special tool that they supply so i'll be ordering one asap.
Great site this, very helpful. I'll be posting pics when my bike is back together.
 
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I think Machine Mart in Edinburgh carry 3/8" drive whitworth sockets, get a set. As stated the head bolts are 1/4 whit but if you want to medernise things the repllacements from Andover Norton are supplied as 13mm heads. :D
 

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The sockets are good but will only get you so far. You will need combination wrenches also. I've had good luck with my Acesa whitworth set made in Spain. Got to the rear head nut in my '72 no problem. These sets appear often on eBay and are very nice quality - thin and highly polished. I also have a Rolson set - not nearly as nice - used for loaning.
 
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