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About dadof2

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  1. Looking at autotrader, ebay and other vehicle advertising sites you can see that some vehicles have their number plates blurred or covered up. All advertising sites should be compelled to publish the VIn(s) and Reg (if registered). If seller wont't supply the information advertiser should be compelled to report this to police.
  2. You can register a bike in the UK for nothing (no £) so long as it is for off road use only.
  3. Bikes now change so little from year to year whether its one year or the next you buy is pretty irrelevant. You can pay top money for the latest or probably get a fair bit off last years model. Always worth considering the cheaper option then spending the spare cash on tuning / set up especially suspension.
  4. Take time to strip and grease the lot including the swing arm bearings. I have a 1987 crosser that was raced regularly until early 1993 and has been played about on several times a year since. The only bearing it has needed was the rose joint at the bottom of the shock. The reason for this is regular greasing of the bearings. Typically every 4 to 6 meetings. The grease used used to be Castrol CL, then Morris K2 grease and latterly S & A complex grease.
  5. Regarding piston ring end gap. Perhaps instead of saying gap "should" be 0.35 to 0.6 I would have been better writing "you can expect" the gap to be 0.35 to 0.6. These are slackish gaps, the 0.6 being the point at which the bore and rings should be properly measured with a view to replacement. Others may have a different view with regard to controlling blowby but I prefer an adequate to large ring gap and plenty of oil as opposed to a tight ring gap and minimal (say 80:1 fuel oil ratio) amount of oil.
  6. Briefly you can put engine oils into 3 groups, Mineral, Semi synthetic and fully synthetic. GTX is an "old fashioned" mineral oil. At any given viscosity synthetic oil has a higher film strength than mineral oil. Considering the small volume (600cc I think) in a 4rt engine its probably worth paying a little extra for something like Petronas Syntium 7000 0W-40 (Fully synthetic) rather than 10w 40 GTX (mineral). If you ride the bike hard try If you are looking for something cheaper try Smith and allans own brand. I have used them for near on 40 years and never had a problem. I presently use their 10w 40 semi synthetic in some of my cars and all my motorcycles. Honda manual just states 10w 40 so GTX should be OK but if you used something like the above synthetics or Mobil 1 you engine would have better protection.
  7. Many years ago on my first bulto rebuild using the method above (recommended in a manual) I ended up with burnt fingers and the job jammed before the crankcases were fully closed. The following method is more reliable and far less likely to damage the bearings. First fit the bearings into the crank cases by warming the cases and cooling the bearings, if any pressing is needed press on the outer race only. Next ensure the crank surfaces where the bearings will fit are really clean / well polished. From memory install the crank into the left hand case first. Do this using a selection of tubes of slightly different lengths, that are the same OD and slightly greater ID than the inner race of the bearing. Using the flywheel nut gradually draw the crank into the bearing. Cease when the crank is about 1 mm from fully seated. Fit the RHS case using the same method. When there is a gap of 1 to 2 mm between the cases keep checking that the flywheels are central in the cases. Gradually tighten alternative sides until the cases close, keeping checking the crank is central and tightening whichever side as appropriate. When fitting any bearing the important thing it to apply the insertion pressure so hat it is not transmitted by the balls / races. Edit - I use an electric hotplate to heat the bearings. It has adjustable temperature and only cost a few £ from Argos I think. My wife bought it to use in the garage cos she got fed up with oily bearings on her cooker.
  8. Before anyone thinks of (wasting) their money on evans coolant I suggest they read the following link. The much lower specific heat capacity and higher viscosity of Evans are serious drawbacks. These types of coolant may have their place in special purpose engines designed for them but thats about it.
  9. See the above link. Your tank is almost certainly polyethylene, Over time ethanol will make it swell. Sometimes plastic swollen by ethanol can be brought back to size with a rinse of methylene chloride left in overnight or for a few days.
  10. Put the rings (one at a time) into the barrel. Use the piston o make sure they are "square" in the barrel and measure the end gap. It should b between 0.35mm and 0.6mm. Any larger gap and have the bore measured. The dark deposits on the piston sides show that the engine has been run with insufficient and / or poor quality oil. There has been insufficient oil to seal the ring to the bore. The mixture blows by the rings then chars onto the sides of the piston. The piston will run hotter than it should because there is insufficient oil to conduct heat from the piston to the bore and cooling water.
  11. If lineaway's suggestion does not work get someone with a mig or tig welder to weld a nut onto the bolts or a length or rod you can grip with mole grips. The heat of the weld tends to be very effective at loosening seized threads. Leaking gasket. Check the mouth of the crankcase and base of the barrel are flat within 0.05mm. Just use one gasket of the correct thickness. Before you fit the barrel paint a good coat of blue hylomar onto the joint face and let it go stiff / nearly dry before tightening the barrel down.
  12. Montesa 4RT 05.pdf See section 6 (electrical) it has some self diagnosis functions regarding the sensors I mentioned. Also some sensor resistance values
  13. The EFI ECU should adjust the mixture to accommodate gentle running and correct the mixture accordingly. Cold weather may be causing an extended warm up (rich fuelling) period. I think the 4rt will have the following sensors: 1) MAP Manifold absolute pressure - this sensor should tell ECU to correct for an over or under oiled or clogged air filter 2) IAT Intake Air Temperature - in conjunction with MAP (and other parameters) enables the ECU to calculate the mass of air entering the engine and hence the mass (Injector open time) of fuel needed to give correct combustion 3) CTS - Coolant Temp Sensor - Its input to the ECU gives longer Injector open duration when engine is cold / during warm up. It may also control fan on / off but this is often a separate sensor. A fault in any one of the above sensors or a fault (poor connection) changing the voltage across it can give rich running. From my experience on cars the CTS would be the most likely to give a faulty output. Injector - if it has a fault, typically a weak or broken spring or a piece of minute dirt on the seat it does not close properly resulting in "injector dribble" and an over rich mixture. In this case the over richness will be more prominent during gentle use. An ignition fault (typically HT coil failing) can give rich running symptoms including plug sutting because the ignition is not sufficient to give complete fuel burn. EFI injection pressure is typically MAP plus 3 Bar irrespective of tank pressure, therefore a few PSI in the tank due to breather pipe should not have any effect. Cars tend to have an accurately regulated fuel pressure mechanism or a fuel pressure sensor that enables the ECU to calculate injector duration. I do not know which is used on the 4RT. If it has neither then excess pressure in the tank would enrichen the mixture
  14. The older pre pro contacts used to use different oils in each fork leg. This is because one leg contains compression damping and the other rebound damping. A few weeks ago a person i know had a new washing machine (less than £400) installed. A few days later at the second wash it leaked. The supplier immediately put a new door seal in the post which arrived next morning. The owner fitted it but it did not solve the problem. When the owner reported this a new machine was delivered, installed and tested within a week, The installers also taking the old machine and packing away. If this level of service can be provided on a sub £400 machine why not on a several £1,000s bike????
  15. I think long track may have two slightly different variations. The slower version is on a course a bit longer than a speedway track and bikes can reach nearly 80 mph. I think on the continent they had some very long "long tracks" on grass where speeds approached 120 mph, more akin to american mile ovals than speedway.