Thanks for all the thoughtful replies. I'll try to address each one:
ZeroClient wrote:
I'll be the first to tell you; you need a working fan. Mine runs about 40% of the time. The good is since you moved the radiator and the wires/thermoswitch is in-tact, all you need is a shrouded fan which will fit the the back of the radiator. Ebay generics work OK, or SPAL brand if you want one a little more decent. Just measure, buy, and mount.
A $5 test light will tell you quick if the wiring is working.
I moved on to the Viton style crank seal from Ebay by the seller named JunkBoy. So far I give it a thumbs up. It sealed better than the SKF brand that came out - in fact I had to change my pilot jet 1/2 point.
I can give you help on jetting. Whats it doing? Is the idle stop screw on the carb all the way in? Does the
Engine stall when flat idling for long sometimes?
If it were mine I'd leave the pull start out as parts are hard to locate possibly. Otherwise, how is the side cover sealed?
I'll have to look for a fan, you have me convinced. I'll measure the current radiator (which I think is stock).
Question Is there a generic fan that you folks recommend for the stock setup?
As for the jetting issue, it is blubbering around mid-throttle. It idles fine. It will die after a couple of minutes idling which is normally how I setup all my two strokes in past (i've owned dozens of motorcycles). I will have to pull the carb off and go from there.
As for the pull-start, there is no cover or anything, it's just open. They took the cover and the mechanism off. I just wanted to have the pull start as a back-up.
ZeroClient wrote:
Are there any engravings on the Engine or head? Billet head?
Is there a spacer between the bottom end and cylinder? Next to the PowerBlock clutch, is there anything clearanced on the cylinder, indicating the PB clutch was running possibly too close to the cylinder? (This is possibly a CR500 jug indication)
Two Engine builders are, ATV Racing and CW.
CW Racing Engines still exists
ATV Racing used to do a lot of CR500 jug conversions. Their conversions I think needed a spacer between the bottom end and jug. Also the jug mounts needed to be re-located in order to fit. To me this would be a frankenstein setup. They worked and made great power but IMO the setup was not the most reliable long term - the mounting of the jug to the base became the problem. On the plus, the CR500 jug will always out-perform the FL400 jug using an actual CR500 cylinder.
CW racing engines IMO does better practice of boring, re-sleaving, rebuilding. CW has 440 pistons for the stock jug/sleave, and CR500 options as well. For CR500 they have a custom LA Sleeve bored out and pressed into the FL400 jug which gets you started at 89mm bore, and I think the cylinder also gets a spacer. IMO CW has better options than the ATV Racing option, but the difference is the CR500 actual jug has much larger transfer ports to start.
Doing a little bit of cleaning etc reveals it's a CW Racing Engines Engine, and I talked to Chris today. Hell of a guy. He and I chewed a lot of the same dirt racing back in the day and he is relatively close to me. I'm trying to research the original owner's name to find out what was done to it instead of guessing. I don't think its a CR500 jug, I think it's a custom over bore.
There is in fact what looks to be a 1mm spacer.
The PB clutch looks fine. Probably just needs some adjustment.
ZeroClient wrote:
What kind of Fox shocks are on the front?? Whats the spring<s> rate? Single or dual? AFAIK Fox didn't really make anything much suitable for the FL400 in stock lift form but I could be wrong. Fox shocks are tunable so maybe you can make it handle better.
What type of race terrain was this machine set up for? Desert, flat track, mx, trail?
The fox shocks are single. I have no idea on spring rate. As for terrain, I have no idea, but I have a feeling it was set for flat track because it is like riding around on an anchor. It just doesn't absorb anything it feels like. The ground clearance is also something I want to see if I can help along a bit. Thus my question about a long travel setup.
Kuma wrote:
I would give the carb a good cleaning if you think it is an issue before doing anymore riding or you may be putting in a new top end.
surprised CO didn't mention AVGAS, I am another advocate, use some good high octane gas, Avgas is a cheap alternative to race fuel, it is around 100-105 octane, I don't think they use any methanol and the quality is dependable.
Fan yes, it may not be on all the time but you want it when it is needed, you mention California and sand, I'm in Socal and dune at Glamis a lot, nothing will heat up an Engine like running up a tall slip face, also out in the dunes it is not unusual to get a bit of a breeze to to call it mildly, let's say 25 mph, going into the breeze at 25 mph no problem now you have a 50 mph air speed to cool, but if you go out you'll need to come back, now you have zero airflow.
congrats on your purchase, yes please add pics.
Agreed Kuma, the carb definitely needs to be cleaned. I am considering doing a top end as the compression should be closer to 150 and I'm at 130.
As for the gas, octane is the devil IMHO as it robs you of power, but you're right if we need anti-ping for these engines. I don't hear it pinging on quality 91 octane in there now, but it might be good to boost it a few points.
A fan is a definite. You guys have me absolutely convinced. Glamis and Pismo are destinations so I want to be ready.
Thanks for all the replies, I'll get pics today.