The problem at hand is the magnet is just not willing to come off not even under the pressure of a bench press.
BHPian SnS_12 recently shared this with other enthusiasts:
Houston, we have a fusion problem
We were planning and hoping to get the bike up and running by end of November, but we have hit a massive roadblock that even after a week of trying we haven’t been able to find a solution. The problem at hand is the magnet is just not willing to come off not even under the pressure of a bench press. From the looks of it over time the magnet met has fused up strong with the crank shaft. Almost three pullers were totally destroyed and even welding one on it didn’t help as it snapped from the weld joint. So, the issue is how to remove it without damaging the magnet, coil plate and most importantly the casing. Tried speaking with Eddie and he suggested pouring hot water over it which we tried along with supercooling and nothing seems to make it budge. So, my friend is going to try to push it out from the other side instead of pulling it and for safety sake I enquired with Eddie if he had a spare magnet and coil and just as luck would have it he had just one left in perfect working condition.
Also, the cylinder head studs had gone brittle over the years and two of them snapped so have ordered 8 new cylinder studs, along with 8 crankcase studs (6 short and 2 long ones) and also exhaust stud kits. Will be replacing all of them for good measure. So, these parts are coming from Yambits where I am ordering totally 92 individual smaller items for my RZ , RD 125 and RD 200. Part shopping just never ends.
Hopefully, with a spare magnet and coil we can try some tougher techniques to get the old one out without worrying about damaging it beyond repair.
Some pictures…
Was wondering how to about painting my top cover of the front master cylinder to get the exposed effect on the Yamaha badging. Enquired with Eddie and sure enough he had one for me
TK 28mm flat slides carburettors sourced locally. Stocking up in case we decide to go bananas on the RZ performance in the future
Our fusion problem
Even welding on the puller didn’t help it just snapped from the weld joint on the press
Eddie to the rescue again
All original wiring and looks much better than the one I currently have on the bike. And kind hearted Eddie gave this last set at a discount just to help me out. This build would not have been possible without his assistance and knowledge sharing.
Speaking on Eddie’s knowledge we thought that the reed valves on the bike were not original as they looked smaller and similar to the RD/RX ones. So, we were planning to instead take this opportunity to use the V Force reed valves. Upon checking with Eddie he confirmed that ones on the bike are original and only the YPVS ones had bigger reed valves. So, to fit the V force ones we will have to shave off significant material from the inlet port to make it fit. Since, we are keeping it stock we will retain the OE reeds for now
Consider this, an engine operating at 8,000 RPM results in a reed petal opening and closing 133 times in one second. And as these valves are almost 45 years old now am getting the below Boyesen petals which are a dual-stage design which incorporates a specially shaped top reed and a ported bottom reed. The top reed is lightweight and resilient for crisp throttle response at partial throttle or low RPMs. The stiffer, bottom reed is ported to provide maximum flow and horsepower at higher RPMs.
While we were stuck with the magnet we decided to move on to fixing the damping issue on the front fork. On checking the internal spring it was jutting out two inches from the top instead of half inch for some reason. The excess was cut off an refitted and it works like a charm now
Also, the front radiator and protective cover was fitted on the bike
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