Cy Welch

If it's surface rust as you describe I would not do anything about it myself other than to make sure that the in-tank filters are good. I would not recommend doing a partial creem treatment either as it strips the anti-rust protection from the metal, so either do the entire job or none of it (I would recommend doing nothing). You can get fuel line and clamps just about anywhere, I got mine from the local auto parts store. Took my old hose in and got fuel line with the same inside diameter and got some screw clamps, which I feel more comfortable with than the OEM spring clips anyways.

You know, it could be the rectifier or regulator causing the problem.

The neutral switch should have a short when it neutral IIRC. That's how it turns on the light, by providing a ground for the light when in neutral.

If it's U.S. spec you don't have to worry about that as they don't have a sharp tip, but rather a flat tip. They also are under a plug on the top between the mounting boot and the vacuum slide cover. On mine the o-rings on the mixture screws were almost completely gone, and if they are bs34 III's according to what I've found they are almost impossible to get to idle right without good o-rings. The good news is that the o-rings and everything are pretty cheap and available from MikesXS. I could NOT get mine to idle right until I replace the o-rings, but once I did it ended up being easy. Running on one side could be spark or fuel, that may take some troubleshooting, oh and making sure there is good compression on both sides as well. But sitting as long as it did I'm guessing it was not prepped. I prepped mine before it sat for 11 years and it still took a lot of work to get it going right again.

I just realized that unless it different than the xs400 that the engine number is the same as the original frame number, so that should enable you to figure the year.

I prefer I nice tire iron myself (the kind for a car, used to loosen lug nuts and pry things (yes the lug nut behind the wheel too))

Why order new carbs? Jus order new slides from MikesSX at $60 each, or just order new diaphrams from Siriusconinc for about $20 or 30 each.

It's way lean. The carbs are not really clean in the idle circuit area or their not adjusted right. You have to drill out the plug over the screws (on top just behind the rubber boot connected to the engine) and adjust them. You also may need to get o-ring and adjusting screw kits from MikesXS as well. Once the idle mix is adjusted right it will start correctly and not hang at high RPMs once warm anymore.

Actually the racing bikes use chains because there is less power loss in a chain drive system. Shaft drive has at least 3 additional rotational direction changes over a chain. Shaft drive is more reliable and lower maint but less efficient.

If the alternator or rectifier is bad the light won't come on, that could also explain the only running with a new battery if the charging system is not working.

Trying to go around corners without leaning the bike is not only dangerous, but make your more likely to need to change your underwear. Just like on a bicycle you want to lean into the turn using countersteer (push forward lightly on the handle you want to turn towards) and lean at a natural angle for the speed. Doing so will make for a much more enjoyable ride and cleaner underwear.

While your point about the crash frame is good, the shadow under the bike doesn't look right. I do believe that the pic has been photoshopped, not saying what is shown couldn't happen or hasn't, but that the picture looks fishy when look at in it's entirety.

20 minutes? Doesn't take more than about 5 to gear up. Boots, protective overpants, jacket, helmet and gloves. I don't wear specialized riding boots, just good sturdy high top boots that I wear most of the time (since my bike is my primary ride) and the pants just zip on over the top of the pants and the jacket goes on over that, the remember to put the helmet on and fasten the strap BEFORE putting on the gloves (DAMHIKT).

Are you saying that nothing should be said/done about the twit who causes problems for all other riders just because he/she rides also? Seems like the code of honour (honor on this side of the pond) would mandate doing something to get the fool stopped before he/she kills themselves and/or others. I don't care what one does on their ride as long as they don't endanger others, but when they cause a danger to others, it's time to get them stopped, personally I would just as soon stick something through their front wheel to bring things to a screaching halt, but when one gets passed at high speed that's both impossible (or nearly so) and dangerous to do (I don't care about the danger to the blithering idiot but rather to other around). This kind of behaviour has no place on crowded roadways. Take it to the country or the track (I know it's much more crowded around your countryside but I'm sure there are roadways where it's safer to be a fool).

Do you have a description/guide on how to do this swap? I would myself be interested in doing the swap on mine, I already have spoke wheels but with the horrible horrible drum brakes, if I knew what parts I needed I could start getting the parts together to maybe do the changeover next spring or so.

Make sense but generally using those types of cleaners is not allowed over here, especially in shops. Safety regs require the use of non-flamable cleaners in most cases, even though they don't work as well. Obviously we are talking about two different things, one being Kerosene, a type of fuel oil which can be used as a cleaner/solvent and the other being candle wax, used for sealing canned food and sometimes as a semi dry lube. Kesosene (parafin to you blokes) is also pretty close to jet fuel so I wouldn't want it anywhere near food either. Parafin (wax) on the other hand tends to be food grade and used in canning, and in beauty salons to soften hand/feet (in it's melted form of course). I learned back in the 70's to use it with motor oil to boil/simmer the drive chain in the provide long lasting lubrication that as well as lubricating well also protects against water/rust and tends to attract little to no dirt. I think it would be easer in many cased if the languages were not as close together as they are since they are right about different enough to make communication even harder than it could be. This of course was done as I understand it in the early days of the separation specifically to not use the kings english. Seems silly I know, but it's what we're stuck with now, not a whole lot we can do about it now.

Umm parafin is a wax not an oil. It's often used to seal homemade jam and such. It's also used as hand and foot soak. When used for a chain (traditional not o-ring) it's often used with motor oil and of course hot. Maybe you refer to kerosene as parafin on your side of the pond? I have never heard that use on this side myself.

The problem your likely to run into is that the spoke wheels typically are drum brake where the alloy are disk. You will need to change the forks and all the front brake hardware for that change. There are xs400 models with spoke wheels (such as the 1980 xs400g) but you will need to change over multiple parts to get there. I have seen front and rear xs400 spoked wheels on ebay quite often.

I would (and have) use(d) parafin on traditional chains as it's in many ways superior for those, but I agree I would not use or recommend the use of parafin on o-ring chains. As a matter of fact, I would only recommend WD-40 for cleaning on traditional chains, while I would be very comfortable with it as lube on o-ring chains since your only trying to protect the outer surfaces from water and such (exactly what WD-40 was designed and intended for). Traditional chains require much better and penetrating lubrication and a good soak and simmer in parafin will do that quite well. On the clean and lube your chains regularly I think we are ALL in agreement, we just don't agree on the best way to do so. I think we are all putting forth the methods that have worked for us over the years, and frankly I'm not sure that this is not a case of all of us being correct mostly. Measuring the wear on my sprockets (did it this weekend) shows pretty much NO wear after at least 36,000 miles, but they are steel and I know most modern bikes have alloy sprockets of some sort and those clearly wear far faster. I also have been paying attention to newer bikes and their chains as compared to mine and noticed that they are quite wimpy compared to my chain, and since my HP is a bit lower I expect much higher wear rates that mine experiences. I guessing that like everything else, they just don't make them like they used to. Many areas are indeed better, (tighter tolerances etc) but things just generally are not built as tough, and they are indeed lighter, and IMHO not as strong, not necessarily a bad thing totatally, but I'm sure it make a difference in how long parts last.

I can't speak to o-ring chains since mine is a traditional chain, however when I got the bike in 85, it had 14,400 miles on it and it now has just shy of 50,000 miles on it. I think the chain had been replaced before I got the bike, but I'm not sure and the original owner (my uncle) doesn't remember at this point, but I still have the same chain on it that was on it when I bought it. That's somewhere around 36,000 miles that I KNOW are on this chain and it's still working fine with minimal stretch/wear and the sprockets still look good. I have NEVER in it's life removed the chain to do a thourough cleaning, but have merely used a good quality chain lube and every few thousand miles use a thinner lube to rinse the chain and get the gunk off. I figure I will probably get at least a few more thousand miles out of the chain and sprockets and based purely on age I plan on changing the sprockets at the same time (oem steel ones though). A lot of modern bikes have aluminum sprockets now though, so for those bikes changing them with the chain makes sense.

My only comment would be that it's now very common for exhaust headers to be treated to keep the heat inside the headers. The major header manufacturers would not be doing this if there was ANY danger of damage to the engine from doing it. I would think it is more dangerous to let the heat out than keep it in, since parts around the pipes may get damaged while the exhaust is moving away from the engine. Many bikes have dual wall pipes which in part keep the exhaust heat inside the pipe and keep the outside cooler (it also helps to reduce blueing on chrome and stainless pipes.

By the time the chain is worn the sprockets are almost guaranteed to be worn too. You could use the old ones if you carefully measured them against new specs and they still matched, but it's more likely that they won't, and from what I've seen the low cost of replacement makes it not worth the chance (although some of us OLDER bike riders with steel sprockets may be more likely to have good sprockets when the chain wears out).

To use a 7" headlight you would have to change to a 650 or 750 bucket.

Not on the stock xs400 headlight, it's something like 6.xx inches. A little smaller than 7 inches and a little larger than the standard 4 light auto headlight. Until the last 15 or so years sealed beam lights were required by DOT in the U.S.

Also make sure the idle mixture is properly adjusted. The symptoms you describe are a sign of being lean and the idle cranked up to compensate. Adjust the mixture screws out until the RPMs stop going up and then back in just a little bit (adjust each carb a little and then do the other). Then adjust the idle (or even while doing this), if it's lean you will be amazed at the difference.