kingscorpion,
Thanks for the informative response.
1. The correct size is 520.
I asked about the chain size because I tried to put on a new 520 chain last night. It wouldn't fit through the chain tensioner. I have a new chain tensioner on order through InMotion.
2. Even at 50:1 every synthetic oil will be enough.
I think that I'll stick with the 40:1 ratio unless I start having problems with fouling.
3. GL-4 is better, but GL-5 probably is an acceptable choice. It will hurt the "yellow metals", but at a high temperature.
I just found a bottle of SAE 90W GL-4 at NAPA Auto Parts during lunch. It is marketed for marine engines, but it should do the trick.
4. Mineral 10W30 or 10W40 is a better choice.
On the way back from NAPA, I stopped by Honda and got a bottle of dino juice 10W30.
5. SAE 20 is the original oil.
I'm thinking that I will go with Belray 10W fork oil.
6. Their maintenance is very simple. Just take a look at the points and condenser, and keep the carb clean.
Got it. Thanks. Will do.
7. Jared Bates at Southwest Montesa is a nice guy. We miss a lot John Haberbosch; he passed away a few years ago and had a deep knowledge of these bikes.
I'll check out Southwest. I've heard a lot of good things about them. I also found a site that I hadn't seen before. (clasicaslegendarias.com) They have a huge Montesa section. Has anyone had any experience with them?
I just put a new set of IRC trials tires on. I really liked them on my Yamaha. I know what you mean about the Dunlops. The original Dunlops were on the bike. They were falling in pieces, but I still had a nightmare getting them off. I finally gave up with spoons and visited a friend's shop with a tire changing machine.
I will take your (and cleanorbust) suggestion and go with a 9 tooth front sprocket. I'm going to order a 9/48 combo.
I have attached a picture of the gear oil container.
