A forum for owners of Yamaha TTR250 trail and enduro bikes!

TTR Steve has always been a bit less than enthusiastic about taking on mechanical jobs. His excuse being that something always seemed to go pear shaped on his projects.

I thought perhaps it was a bit of an excuse not to get oil under his finger nails 

However, having worked with him for a few days building his 350 big-bore engine I now understand what he means!

These are just some examples of his bad luck that I can recall:

a) Fitting flywheel. No trace of original Woodruff key but, no problem, Steve had a brand new one in packet we could use. Strangely, it was damaged (photo below) and it was the only one he had in stock so we had to find another.

This involved taking a flywheel off a spare engine. Once the flywheel was off, he found a sheared key and the taper on the flywheel had been damaged where it had been spinning on the broken key remains.

I can't recall why the original flywheel wasn't available (probably lurking under a box/shelf somewhere along with the missing key!) but we still needed a good key and flywheel. 

Fortunately another spare engine was available so the flywheel was removed from that. The key was usable but the flywheel looked as if someone had hammered it on with a block hammer! It wasn't usable so Steve had to resort to taking a good flywheel off the shelf from his shop. So two flywheels ready for the bin 

b) Generator cover and stator. We were about to fit the cover when Steve noticed a blob of weld which, presumably, had been used to repair a small crack at the starter end of the cover. Wanting his new 350 to be as close to perfect as he could get it another cover was found but, unfortunately it didn't have a stator fitted so we stripped it out the other and were about to fit it in the newly cleaned up cover when a sheared Allen bolt showed up!  

Now, those of you that may have followed a recent thread on here, will now know that these bolts are high tensile bolts and none of Steve's drill bits would make a dent in this little blighter. So, a trip to his local tool shop followed where a range of drill bits, an EasyOut kit and a Helicoil (fearing the worst!) kit were purchased.  Even the newly purchased cobalt bits made no impression so we tried the trick of arc welding a washer over the stud but, because of its proximity to the case, it wasn't possible to turn the welded-on washer without it breaking off  However, another attempt at drilling saw the drill bit going in about 1mm but no further. At this stage we gave up and took it up the road to Rob, Steve's clever engineering mate. That was an expensive visit for me as I ended up buying a BSA C15 he had tucked away unused in the back of his workshop 

Rob tried welding a washer using his MIG welder but had the same problem as we had. Steve tried one of Rob's drill bits and actually managed to drill right through this time. We figured that we had de-tempered the bolt with the heat from all the welding! Rob tapped a tight fitting Torx socket into the hole and wound out the offending stud with no damage to the threads 

c) Clutch cover oil seal. Steve cleaned up the cover and spotted that the oil seal was damaged. This then involved him in finding another cover with a good seal to replace it with. You just wonder what happened to cause that damage 

There were several other little occurrences but these were the ones that swallowed up so much time and demonstrated what Steve meant by his bad luck!

Sadly, I caught his unlucky bug and on my last visit managed to tear a special 350 base gasket meaning Steve had to take a standard one out of a new Cometic kit and modify it to fit. 

I mentioned to Steve that we were taking chances not putting rags in the crankcase holes and that, knowing his luck, he would drop something in so we duly stuffed them up. What we didn't notice was that the oil filler cap wasn't fitted and, within minutes, I managed to drop a socket in such a way it disappeared down the hole  

Steve's workshop magnet had gone walkabouts (of course!) so after a long search he gave up looking and we thought of how to improvise. As you can see from the photo, the socket hadn't gone far and was ready for removal if only we could figure out a way to do it without knocking it right in and then having to take the case off. This is what we came up with - a loop of string down a thin copper tube that acted as a noose to capture the socket 

I hope that's the end of all the "issues" and that the build will be all plain and easy sailing from now on but, yes Steve, I now know exactly what you mean about your bad luck!

Brian