Hello, Came cross a great deal on a. 830 kit , with thd head pistons and rings. Tempted to buy it, but was wondering if anyone here has done it? Will I need a special base/head gasket? Will it need any modifications to the head? Thanks for any advice, Dennis
There are good and ... uh ... not so good ... triple big-bore kits.
Good are ones from P&M and Neil Beadling in GB; in the US, guys like TripleTecs might be able to help.
Hyde barrels are easy to tell - they have fewer fins and a wider spacing than standard ones. They can be good, but they can also be a pita - expect to have to helicoil/Timesert all the threads in an old one.
'Least good' of the not-so-good are probably the ones marketed by Wassell in GB, although John Healy says Wassell didn't actually make them. These are simply standard barrels bored out; because the casting then doesn't support the liners, they go oval, leading to much smoking. General consensus is that these'll last about 10,000 miles - sort-of ok if you do 500 to 1000 miles a year, less good if you do more.
Worst would be 'Wassell' barrels that've done the 10,000 miles already ...
Hi djg,I will send you some informations only to help you,I have a big bore kit from NOVA CLASSICS NEIL BEADLING,I PAID FOR THEM 1500 STERLING POUNDS PLUS THE PRICE OF THE OMEGA FORGED PISTONS.Well,when I had on my hands I was very happy, very good castings,many big fins etc but when I measured with cylinder bore gauge tool to see if the piston clearance was ok,I found that was something wrong with them,.004" on the top .003" in the bottom.I found also that they were not std size, the pistons were 71.5mm not 71mm and the liners were over the top of the face of the barrels they needed skimmed.Finally I spent 400 euros for new liners and rebore service here in Greece.I couldn't find him on the phone and didn't responded to emails.Very bad comments I heard for MR HYDE ESPECIALLY FOR HIS TRIPLE LONGSTROKE CRANKS.The only serious company is P&M AND if you find a billet alloy big bore kit there is the best of all,another great company who had big bore triple kits is MAP.The best pistons for them are the forged omega and Arias and in the 70's venolia pistons was great for big bore triples.I hope to help you and please be careful out there!!!!!Cheers Kostas.
I used routt 867 big bore liners in a std cyl and they worked fine. You can just use a file or powered hand tools,(a rotary burr or die grinder,)to adjust the bore on a std copper head gasket. Don't use a base gasket, use 3bond supersealer or similar, if you use solid copper rockerbox gaskets as well you will hardly ever need to adjust tappets. Triples are really nice with a big bore kit. Kostas "the liners were over the top of the face of the barrels they needed skimmed." Don't the Hyde liners have a spigot at the top to go through the gasket? I'm pretty sure when we fitted liners in my cyl we left them a little above the surface to get a better seal.
Hi Mark,the Hyde big bore triple barrels doesn't have the last fin on the top to check easy for leaks.I make my barrels absolutely flat on the top and with a Victor Reinz head gasket I resolve all the problems.With P&M AND NOVA big bore kits you can also to torque the cylinder head at 20lb/ft without problems.Regards Kostas.
Hi Peter,from Mark's posts you can understand that he has a great experience on these bikes and always helps me and the same many other members,I just sent my opinion and the experience what it works on my bikes.And I wouldn't to speak for Hyde's "special parts"cheers Kostas.
Is it true that the STD 650 piston is the one used for the 867 kit?
If it's simply a big-bore - standard 70mm triple stroke - no; 867 requires 72.5mm and, as you know, "the STD 650 piston" is 71mm, which gives 831.
Btw, in a recent TOL post by Pat Brown of Triples Rule (whom I forgot in my previous post - sorry Pat ), he admitted he'd made a mistake calculating his big-bore kit as 867; his uses 72mm pistons so is 855.
Finally, one of the options certainly with the Nova (Neil Beadling) kit - and possibly with the P&M kit - is 71.5mm Omega pistons, giving 843.