Things to Know about Your RD: RD's that have sat for a long while, can have issues such as;
· Leaky crank seals - This happens due to lack of use and time [age] of the rubber. Cannot seal around the rotating crank shaft, will suck air(left side) or oil(right side) into cylinders. To rectify this engine needs to be disassembled and all the seals replaced.
· Top End rattle -2 strokes wear out their pistons in about 3k miles or so, most old bikes have been seized and left to rot. A compression check can show leakage due to seizures/wear, if below 100psi new pistons and rings need to be installed.
· Crank shaft- When replacing pistons [top end] it is wise to inspect and measure your crank shaft. If the crank shaft is out of spec, it is best to have it rebuilt. If crank is out of spec the new top end will have a shorter life.
· Fuel system- Fuel tanks rust over time as well as the petcock rubbers get old and do not seal any more. Cleaning the tank with a mild acid or Electrolysis can restore most of the damage. Coatings can be used as well.
· Carburetion- Over time Carbs build up varnish or sludge if pre mixed. Cleaning of all passageways is needed. Needle and seats need to be inspected for wear, replace as needed.
· Ignition Timing- RD's use contact points these need to be looked at and replaced or adjusted. Setting timing is critical on these bikes. Using a dial indicator is the only way to set timing correctly.
· Drive train- Chain and sprockets, on old bike these are neglected and usually need attention. Looking at the rear sprocket if you can see wear where teeth have pointed or between teeth. Should be a nice U shape if worn will look more like a y.
· Clutch - Friction plates wear with use, when doing any motor work it is an opportunity to replace parts you normally don't have a chance getting to. Also the basket can have to much sloop due to rubber dampers have fallen a part. Replacing these can be done, some machine work maybe needed.
- RD gear boxes are pretty tough, but they do get abused. Inspecting all "dogs" for wear as well as teeth. Sloppy idler gears or a bad 2nd gear can be due to wheelie shifts or partial shifts. Bearings should also be inspected for wear.
· Suspension- Front forks need to be inspected for rust/pitting of the chrome as well as the seals. If the seal are in need of replacing & the chrome has pitting. New seals will not last long. Replacement of fork tubes or re-chroming recommended.
Rear shocks over time may leak so there is not dampening left in the shocks. Like a pogo stick the bike will bounce over bumps. New unit are recommended.
· Brakes - Older models had front and back drum brakes. These brakes can be adjusted to accomplish good braking. Newer models have front disk brake & rear drum /Disk. Hydraulic brakes need to be flushed and inspected for seal leaks. Rebuilds are recommended for master cylinders and calipers. Brakes can be resurfaces, and rebuilt with new parts.
· Steering -
Steering head bearings wear over years of use, also they can rust. Recommendation is replace with newer tapered bearings.
· Wheels - Spooked wheels need to be maintained -trued and tightened periodically. If you see rust around the spoke nipples this needs to be looked at. If the rim has rust where the nipple goes into rim this can fatigue and cause failure. Where the spoke will pull through the rim, replacement of rim and spokes is best in these cases. Bearings in wheels can be replaced to newer longer lasting bearings.
· Electrical - Wiring over time and neglect or modifications can be troublesome. Rewiring can be done or replace old harness with new of used. Charging systems can be checked and parts can be acquired and replaced. I have lots of experience with wiring and electrical. Whether repairing damaged wires or replacement.
In short you have a nice 30+ year old 2 stroke bike and you want it to be dependable and fun. Age/the elliments has taken its toll on your Yamaha 2 stroke, Safety first brakes and tires. Then look at steering, drive train then motor.
I can help you on any of these items listed above; I will tell you what your bike needs when I inspect it. Don't be surprised when the list total reaches or exceeds $500 -$1800 or more.
Now look at what a new bike cost? $4k-$20k you have to figure this is a payment or 4 on a new ride, after the initial cost of repairs you can enjoy safe fun rides for many summers. A Dealer might charge this for a tune up [and not a very good tune]. With RD's Only we are looking at the whole bike to make it safe and dependable for you to enjoy.
Give me a call John at (512) 718-9570
Go to Check list for details on looking over your bike