20 Most Recent 1973 Yamaha TX 650 Questions & Answers

Sorry but this is just to old.

www.amckayltd.com/carbguide.pdf

with black plugs it might be that there is no back pressure because of the cut off pipes. It also could be valve guides leaking oil into the cylinders.It is most likely that the carbs are not tuned to the opened exhaust

The idle problem is a lean fuel mix caused by an air leak in the intake system. Bad gaskets /seals on the intake manifold, bad valves, bad piston rings, loose spark plugs, and bad head gasket are all things that can lean the fuel/air mix. The smoke indicates a need for new rings. I would have the cylinders bored then install new pistons and rings. Now finish the top end work by getting a valve job. You should get a liquid fuel tank liner to eliminate any rust problems in the future. Also, install an in-line fuel filter. Google “ kreem fuel tank liner “ or go to www.http://www.4secondsflat.com/Fuel_Tank_Sealer.html


My complements on the well cleaned carbs. Do the work mentioned above an you will effectively have a new engine.

A “very helpful” rating for this answer? Thanks!

you need to check and replace any bad fuses, main or ignition fuse, make sure kill switch is in run. just charging battery doesnt mean that it is goog,check voltage.

looks like a sealed beam headlight you'll find loads on ebay uk

check the float hieght or to see if the jets are clogged

sorry we are not a parts locator, but from my own expearience try Dennis Kirk motorcylce parts.

Okay, I will tackle a tune up on a 36 year old Yamaha. Warning: I am 59 and haven't touched that bike since I was 23 and a mechanic at Lynns Yamaha in D.M. Iowa. Your bike has CV carbs and I know very little on the carbs.

First let me suggest you get a service manual. Go to www.repairmanuals.com and input " 1973 Yamaha 650 ". You can choose a Clymer or a Haynes manual. I don't care for Clymer and have never used a Haynes. The Haynes is $23.77 which is really a pretty good price considering not many of the manuals still exist.
Also, for future reference, go to the following site where you can see a parts diagram for your specific bike. You will select the brand, year, model, etc., once you go to the site. Part numbers and prices are also shown. Parts can be ordered if the price is shown > no price = the part is not available.
http://www.babbittsonline.com/pages/parts/viewbybrand/1/Yamaha.aspx

Also Google " motorcycle salvage yamaha " and Google " vintage yamaha motorcycle parts ".

Start with new NGK B8ES spark plugs. New points can be gotten at the Babbitts site. Set the points at .015 max opening. Hook a timing light up to the left cylinder. Remove the left case cover to expose the flywheel. Start the bike and point the light at the static reference mark on the casing. IF I RECALL CORRECTLY, rotate the base plate that the points are mounted on to adjust the timing. The timing should advance when the engine is reved up. If it doesn't, the spark advancer needs service. Now put the light on the right cylinder. IF I RECALL CORRECTLY, changing the right cylinder point gap is the only way to set the timing for that cylinder.

I hope this helps. Please rate my extra long answer. Thanks.

You should not mark the cam gear with a punch. This will throw it out of balance and eat the bearings up. I would suggest putting diesel fuel in the cylinders. If this does not free up the cylinder then the cam gear has a mark on it, as well as the crank. These two marks need to be together. Crank at top and cam at the bottom, when you go back together with it.

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.