20 Most Recent 1974 Yamaha XS 650 A - Page 2 Questions & Answers

exhausts are a dark art.......to gain maximum power ..they will need to be of a tuned length...and of certain diameter at certain points.... if your having them made by a reputible(sp) company,they should be abe to get you in the right ball park... take into consideration groung clearance etc

If your motorcycle has a center stand, use it for long term storage. If you're not riding for several weeks and don't have a center stand, you may want to consider carefully propping up the bike using blocks. Don't do more harm than good by dropping your bike while attempting to prop it up! If done correctly, lifting your motorcycle will alleviate stress on the suspension and tires. Inflate your tires to the maximum recommended pressure will maintain their shape, since cooling temperatures will make the pressurized air contract. If the ground might potentially freeze, try to keep the tires off the ground using wood blocks.

It is a 1979 Yamaha XS400F. Although it was built in 78 it is a 79 model year with that serial number. 392cc plus the serial number both ties up with it being an XS400.

http://www.biker.net/650_service/650service%20main.html

try calling factory pro
http://www.factorypro.com/
there is the web site. good luck
Mark Woodring

become a real wrencher like us boyz and purchase a clymer manual--

Hello Wayne,

Find your VIN number, usually located on the upper front of the bike, and use this link (VIN) to find the information you need on your bike. The VIN is 17 characters long.

Hope this helps. If you find this information useful, please vote on this post. Thank you.

Regards,

Oz

I just got done with the same problem on mine and it was the carburetor.
It was dirty and the jets were clogged.
I had it cleaned and now runs like it should.

Just soaking it will not be enough - you must dismantle the engine for a thorough cleaning.
If the original marks have wore off the you must make new ones - if you're careful when dismantling the distribution, paint will be enough: paint 2 thin lines (of different color) over the chain and the sprockets at whatever place you want; then, when reassembling, first align the crankshaft sprocket with the chain and then the camshaft with the chain - here you will probably need several attempts to get it right, don't force and don't hurry.

Have you tried to richen up the low speed on the carb?

This is a highly ill - eagle act to do. In the old days we would put an electric drill on the drive cable, but now they make them tamper proof so they only go one way. The bezels are crimped on so you can't get inside them. I expect modern one may be electronic. How will your insurance company know what mileage you have done? I have never known an insurance cancel or fine due to mileage. You should have just disconnected it when you got close to the limit. Buy a used one and use them for 6 months in turns. There are two or three here 23K and one with 36k https://www.google.com/search?q=2002+yamaha+sr125+speedometer ..

Not mentioned in the Service manual http://www.badrad600.com/Yamaha_Radian_Factory_Service_Manual_OCR.pdf https://www.google.com/search?q=1986+Yamaha+YX600+Radian+remove+USA+speed+restriction Something like this?

Removing 95bhp restriction ' Yamaha Star Cycle V-Max ...

vmaxforum.net https://www.vmaxforum.net > threads > removing-95bh... Jan 14, 2013 - Air jets could easily become blocked. Step 3: Removing the speed restriction. On the back of the speedo-needle a disc with two different . ..

Check the diagrams here https://www.google.com/search?q=yamaha+sega+81+firing+order ..

Question edited for a lot more clarity, add maker. Question moved to Yamaha Motorcycle. Unlikely to be a carburetor problem as this appears to be fuel injected! https://www.google.com/search?q=Yamaha+Mio+125+MX+no+start ..

Make sure the fuel is getting to the valve and passing through it. Possible blockage in fuel line or in the tank.

It isn't called a Magneto, that was for really old bikes. It is a 'stator'. Service manual https://drive.google.com/drive/folders/1OFbBW2YhLpL1-Xbsw9vexi84Y7aXGTdG Parts List https://www.cmsnl.com/yamaha-rt100-1990-l-usa_model9624/partslist/ https://www.google.com/search?q=1990+yamaha+rt100+wiring+diagram ..

First make sure that the new battery has been fully charged and is not defective. Next make sure that the proper voltage is reaching the started. You may have a bad post connection or loose connection at the starter. Try jumping you battery with another known good battery.

Above the master cylinder on each brake.