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i24

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Everything posted by i24

  1. Weld repairs on airliners are common. BUT, there has to be a documented repair procedure. This has to be signed off by the aircraft manufacturer and approved by the governing authority (eg FAA). The procedure would typically state: What the part is and what damage is to be repaired What weld process to use, current, voltage, gas, filler metal spec etc. Weld preparation and inspection . Weld pre-heat, filler metal preheat and how temps are to be measured and recorded. Welder qualifications (typically welding a similar test sample which is then cut up and inspected). Welder qualification renewal (when was he last retested). Heat treatment (time, temperatures, quenching etc). Reinforcement jigs may be required to prevent deformation during treatment. Post repair inspections (eg X-ray, or dye penetrant inspection) and dimensional checks - in case the part deformed during heat treatment. Post repair coating/painting (another whole procedure). Then there is the paper trail which goes in the aircraft repair logbook: The part serial number, hours flown and number of take off/landing cycles. The above weld repair procedure. Material certificates for the filler material, gas etc. Pre repair inspection report Records of pre heat temperatures. Welder identity, qualification and renewal tests dates. Heat treatment reports. Copy of the chart from the temp/time recorder on the heat treatment oven. Post repair inspection report. All of the above paperwork is subject to getting audited, by the likes of SACAA. So the welder may be very experienced, fully qualified and have a very good idea how to do the work and what process to use. But he is not qualified to write the repair procedure. Also he is likely not the person responsible for post weld heat treatment, post repair inspection etc. This has nothing to do with bike repairs. There above costs way more than a replacement frame, never mind the cost of repainting. Carbon frames are much easier to repair to original strength. It is just difficult to not add extra weight and make the repair look invisible. But this is still a job for skilled/experienced repair guys.
  2. I am very surprised that a responsible manufacturer would have offered "1. Repair". This was never a viable option. It's only purpose that I can see is to deceive a future owner. A typical Aluminium bike frame is made from "6061" or similar tubing. After welding it gets "placed in an oven at 530C for 40 min" then quenched to room temperature (eg in a water bath or spray). Then optionally, re-heated to 177C for 8 hours (which makes it stronger). There is no way any of the original paint would survive anything like this. Your photo's show that there was no recognized heat treatment. (If they claim otherwise, ask them for their heat treatment procedure, it should be documented). You might get away with a simple weld repair, without heat treatment, in a low stressed part of the frame. For example if the damage was due to an external force above design force, like an accident, that is not expected to happen again. If the damage is a fatigue crack in a highly stressed part of the frame, a weld without post weld heat treatment will be much weaker than the original frame and that crack is going to reappear! Some more interesting reading on Aluminum bicycle frames. https://web.wpi.edu/Pubs/E-project/Available/E-project-042612-124752/unrestricted/Material_and_Design_Optimization_for_an_Aluminum_Bike_Frame.pdf
  3. Was this repair done under manufacturer's warranty, or was it an "approved" repair by one of their dealers? if so Momsem have some explaining to do. Welding aluminum is a science. Depending on the grade of aluminum specific pre and post weld heat treatment is essential. From the post repair, pre-repaint photo's it was clear this weld got neither. That is one of the most highly stressed areas of the frame, if it had cracked once there is no way this repair would not fail again. This was just a "cover up" job. The only motivation I can think of doing a repair like this is to enable the bike to be sold to some unsuspecting buyer - which the OP clearly had no intention of doing. This is an interesting story on how Giant make frames https://www.cyclingnews.com/features/tech-inside-giants-taiwan-bike-factory-part-three/ "Once welding is completed, frames are sent off for the first round of heat treatment (to T4 spec, for those that are interested), checked again for alignment, then sent for the final round of heat treatment (T6 spec)."
  4. As you point out, the boot lid rack damages the car. But the roof rack will do much more damage to both the car and the bike when you eventually drive under something too low - which WILL happen, at least once. Personally I would go the towbar option. But I already own one trailer ...
  5. Ask them to provide you with a repair procedure document. It should document the welding process and post weld heat treatment. A professional shop should be able to do this. A really professional shop would also provide you with inspection reports and temperature charts from the heat treatment etc, to show that the repair was done according to the agreed procedure. If they can provide this, it will help with future sales and insurance negotiations. If they can't provide it, then is is likely that they will spend more on the paint job to cover the workmanship than the repair itself. So monitor it for cracks afterwards and post something here when they reappear.
  6. There are two ways to wear out chain prematurely: Remove the OEM lubricant from inside of the rollers by soaking the chain in solvent, and/or washing it with mechanical assistance. Then fail to adequately re-lubricate it and keep it lubricated*. This is unlikely to happen if you never take the chain off the bike. Ignore all maintenance until the chain goes rusty. More likely to happen if you ride in rain and mud and park the bike outside. If you prefer riding your bicycle to messing with dirty chains, or you attach any man hour value to your leisure time, leave the chain on the bike, clean the exterior with a brush and maybe some degreaser solution, rinse with water and re-lubricate with your lubricant brand of choice. If you are keen to spend hours messing with dirty chains, then there are lots of posts on bikehub and youtube videos to give you suggestions on how to entertain yourself. * If you do manage to wash out the OEM lubrication from inside the chain, the following are methods which may suffice to replace it: Soak and manipulate the chain in a bath of hot low viscosity lubricant, until it reaches inside the rollers, then let it cool down so lubricant thickens up and stays inside the rollers. Soak and manipulate the chain in a bath of lubricant which is mixed with solvent. Then let the solvent evaporate so that the lubricant thickens up. Lubricant with liquid lubricant and repeat at regular intervals, so the internals of the chain get enough lubrication. Chain saw "chain and bar oil" (https://www.takealot.com/ryobi-chainsaw-lubrication-bar-1-litre/PLID34170073) is probably as good as any other lubricant that you can use for this, and cheaper than most alternatives. Have fun .... !
  7. Note, not all testing stations in Cape Town do motorcycle drivers tests. I think Green Point and Somerset West do.
  8. When you install the replacement, make sure the fitting on the end of the cable can rotate freely in the notch on the clutch handle. Otherwise the cable will bend at the end every time you operate the clutch, which will result in another premature failure.
  9. This gets my vote - ban religion, politics, racism and sexism. Add a reporting function where readers can flag a post and list which of these it violates. Cyclists have a lot in common, from swimming pool pumps through woodwork, load shedding, getting divorced, emigrating and not getting recovering from covid. Discouraging these topics would remove a lot of interest, a lot of activity and many page views from the forum.
  10. Reading between the lines of the V85 reviews. I think the 6th gear is a genuine "overdrive". So it will cruise on the freeway at low revs on cruise control, all day. But if you need to unleash all 79 horses (or what remains of them by the time they get out of the shaft drive into the back tyre) to do some overtaking into a headwind, then you need to change down first. But I have never seen a V85, let alone ridden one. I think the first one just arrived in SA and that was in Gauteng. So let us know what it is like if you try one out.
  11. I have a 1979 V50 MkII. I bought it in about '83. Mine's a keeper and I think some of the parts are still interchangeable with the V85. Mine has excellent handling, good brakes and most parts still available. I import parts from https://www.stein-dinse.biz/. UK also has good on-line suppliers. There is an online Guzzi forum, with many UK based participants at http://www.guzziriders.org/. Check them out if you are thinking about a V85.
  12. Just make sure the helmet fits - not too big. Don't worry about the mark on the fender - then you won't feel so bad when you drop it! ???? Don't go near Trac Mac - your wife will not appreciate further disruptions to your cash flow. And for that matter, don't go near Flying Brick either. ???? Petrol goes down in price next week ???? Ride carefully and have fun!
  13. Thank you for using the Cape Town Cycle Tour Trust Online Entry System. You have been successfully entered into the event. Event Name: Cape Town Cycle Tour Event Date: 10 October 2021 2 down 17998 to go!
  14. +1 on the Bosh 12V drill. However I think mine got branded "14V". This is just a confusing sales "interpretation" - when the Li batteries are fully charged, they approach 14V. The tool, batteries and charger are identical to 12V ones. I use mine for most drilling and driving jobs. It is not too heavy. I keep a screw driver bit kit and a drill bit set in the box with the drill. I also have an adaptor to connect it to 1/4" sockets and allen key sockets. The only challenge is to keep swaping bits between screw driver and drill. For heavier drilling, masonry work, hammer drill etc, I get out the extension cord and my old corded drill.
  15. My nephew lives in Melbourne. He went camping a few days ago and they had a snap 5 day lock down. He had to stay at on at the camp site for the rest of the period and "work" on his laptop. Back in Cape Town, our second wave is falling fast. We are down to "just" 200 new infections per day and below 20 fatalities per day (Western Cape numbers). Lock down down to level 1. They estimate up to 50% of our population has been exposed to the bug. So while a "3rd" wave is a distinct possibility, it is going to take another new variant, or a complete change in social behaviour to spread the bug through the other 50% to make it happen with the intensity of the 2nd wave - even without vaccines. Which is just as well as not much is happening on the vaccine front here. Selected health workers only getting it at the moment. Then we still have to see which vaccines are actually effective against the SA variant, and how long that protection lasts. So while it is still dangerous out there - (I stay away from crowds and wear a mask when I can't avoid them) we don't have to worry about regulatory lockdowns for a while. One thing we have in common with NZ. International travel from SA is very easy to plan - postpone indefinitely!
  16. That exercise probably burnt best part of 100 Gallons of kerosene...
  17. I don't see a funding for much bike coming out from this
  18. But if the bike is a Harley, freedom may be curtailed when you go round corners.
  19. I live close to Spaanschemat River Road and cycle on it regularly. It is very busy with lots of cyclists. There have been incidents near the American Embasy - close to the informal settlement near Westlake. Some perps were caught a while back, which may have slowed things down. Just be sensible. Avoid cycling alone when there are no other cyclists around and leave your valuables at home.
  20. Maybe something to do with PayPal terms about when a payment can be cancelled or reversed.
  21. Wow. That looks nearly as far South as Marion Island. What is it like there in winter?
  22. I think that was the one I saw a youngster running around with near Kommetjie at 1400 that afternoon. I saw it again round 2014, but sorry I could not stop to pick it up. It was back this year. Lying in the road again in Kommetjie. A guy motoring past on on an e-bike nearly rode over it. He took evasive action and hit a traffic cone marking between the lanes. There was a loud noise but not much blood, so I think the water bottle was OK. I will look out for it again next year, will let you know where to go pick it up ...
  23. I notice that the top right quadrant of every link is chamfered. Is this chain directional? Ie is it designed to be installed with a specific side facing towards the sprocket or towards the wheel? Or are those wear marks? Do you take off the chain off the bike for cleaning? Maybe it has been overwashed, perhaps with a solvent which has caused stress corrosion cracking. If it is due to a manufacturing fault we should hear other reports of similar failures.
  24. The weight of the battery should be limited to. Easy for anybody to check.
  25. Of course I should have added that e-bikes entries should only be accepted for the short route, not the full one. We don't want to risk them running flat half way round.
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