I have been wondering about this. How do you set up a slider in a lathe? All of the external surfaces are non-precision as-cast surfaces. How is the slider held and how do you get the bore aligned straight and centered?
there are a couple of ways,
In a four jaw chuck and a fixed steady (and a bush to fitted to run the steady)
or the slider mounted on on the cross slide (vee blocks and lots of packing), and boring bar in the chuck
Thanks for the info guys... I've read many threads stating 1 thou per inch = 0.0028 for a 72.48mm bore. So If the piston is 72.457mm leaving a tolerance of 0.023mm equating to .0009 of a thou!! So if I put a standard 72.451mm equating to 0.029mm or 0.00114 I'm confused as that would also be tight!!
Does anyone know where I can access beta tolerance data? Am I measuring the bore wrong as it is stated as 72.5??
The bore is 72.5mm + or - whatever the tolerance is for the plating, (that's why they have size graded pistons)
the clearance depends on the piston material, if its hypereutectic then 0.023 would be fine
Measuring it with a caliper you cannot get the accuracy required, therefore if the seller says they are paired, then its probably correct.
40:1 isn't too far off, i would never go below 50:1 on an air cooled bike of that era. Even at 40:1 your bike shouldn't smoke that bad, unless its an inappropriate oil or something up with your bike (seals or clogged exhaust). Ive run fantics and bultos as high as 35:1 and they didn't smoke excessively
Same here, I run my air cooled bikes at 40:1 without any problems or smoke.
If they are the old wheels with integral bearings the tube is probably there to keep the old tyre inflated. They are tubeless, everything is. Old rims get rusty and don't seal and the bearing type rims are a pain to do at the roadside. We are unable to source the rims any more and advise new suspension units with the more common bolt on wheels. I would thoroughly check the suspension before you invest in the tyres. If it is OK and you change the tyres yourself it is the lowest cost option. I'd check the bearings at the same time and replace them too if they are not 100%.
Once you have the old tyre off you can inspect the rim and make your decision on the tube. I'd be tempted to put in a tube if the rims are crappy. New tyres will - of course - "repair" the puncture that probably was the reason for the tube. Do you have a compressor? You can inflate a tubed tyre easily with a foot pump but often need a compressor to seat the beads on a new tyre. The new liquid latex sealants are very good and seal a puncture rather than go flat - even a tube will puncture. I run latex in the mountain bike and it is very good. Tubes increase the heat slightly in high speed applications like a trailer, but beyond that are a non issue.
The rims are in reasonable condition, inside and out.
the drop arms and stubs axles are also ok, do I need to check anything else on the suspension units?
I would change the suspension, but they have been welded directly to the chassis!
I have one brand new 4x4PCD 25mm hub assembly which someone gave me, but I cannot find anyone else who sells them. A few companies have tried to sell me the 1" hubs!?!?!
clutch and gear shifting
in Beta
Posted · Edited by suzuki250
Use the clutch, its not a race so you don't need the power on all the time.