Colsibro Guides Problem

Good morning. I'm putting a 650ss head back together and I've noticed with the Colsibro valve guides there isn't enough "step" for want of a better description to securely locate the heat insulating washer and the spring bottom seat too. The washer thickness takes all the length of that part of guide which is left on that part of the protrusion. As a result the bottom spring seat could slide about. I don't think this is right. Any ideas? I thought I was doing the right thing using bronze guides. Maybe go back to iron guides? Not use the washers? Thin the washers down? Given the wrong guides? TIA

Does the 650 use the insulators, as far as I can make out according to the parts book of the Atlas and G15 they were not used on these two models and only incorporated in the later Commandos.

Interesting. The parts books for the 650 models, including the SS and the later Atlas, don't show the insulating washers in their illustrations, but they are included in the parts list for all the 650 models. Part number 23392, quantity 4 required. That's not an unusual situation. There are a fair number of small parts that are not included in the illustrations, but are in the parts list.

It sounds like your problem is with the bronze guides not having as tall a shoulder as the originals. The original guides have a tall enough shoulder to locate both the insulating washer and the spring cup. I've seen 750 bronze guides that do not have a tall enough shoulder to locate both. I don't know how common a problem that is.

Ken

Well I've taken the inlets out. I know that sometimes you have to anyway if you use a different camshaft and as I haven't decided yet on which one to use I thought it wouldn't hurt and thinned the exhaust ones down.