Monday, 18 September 2017

350 lives again

Well the 350 started much easier than before so that issue has definately been fixed, however still not running right, little adjustments on the carbs seem to make little difference, so to cut a long story short I noticed that the engine seemd to be blowing back through the left hand carb. this turned out to be rather worn carbon reed valves, so they all got changed out aswell and it now runs loads better - so happy with that result. Ready for the track.

I have also been playing with FZR engines. Remember back I recovered a some what dodgy engine with a bike, and plus one of my mates from proclassic donated a whole load of engine bits to me, so I was thinking to make a spare track/road engine out of the two.

I started by opening up the water damaged one, and it's a real shame as anywhere the water (sludge level) had not covered a part it was rusty as hell, the cam shafts are toast, along with the cam followers, however the head is useable, one of the barrels is marked and the others all have water marks on them so I think that would need a rebore to be serviceable.

The bottom half wasn't as bad as it had sat covered in sludge so the metal had not had the air to react with. One of the big ends is a little stiff, so for the moment I am not using that crankshaft, some of the gearbox gears were rusty but in general cleaned up well and will make good spares. With all the useful bits bagged and catalogued (yeah right...), time to look at the other engine. This one had literally been thrown together for easier transport, so the covers were missing screws etc... with this engine I have good cam shafts, a good crank, and a resonable gearbox, although I have swapped over some of the gears as there were marks on some of the dogs etc... and this model is known to have a weak 2nd gear.

The only parts I need to buy are :- new main bearing journals, a couple of oil seals and a new gearbox sprocket!
oh and both secondary gearbox shafts have useless threads (sprocket nut), so will need either replacing or bodging.
A quick look on ebay, and got a complete gearbox for $50, however someone suggested a fix, so here it is, a 3.0mm hole drilled through the damged thread and then the sprocket will be held by a washer and split pin!
I was a bit worried about drilling through the hardened steel, but it was OK, and I didn't even break a drill bit. So the gearbox is now in place in the upper crankcase.
Right working out the size of the main bearing journals is a bit of a faff. Yamaha have etched 2 sets of numbers, one of the left hand crank web and the other on the crankcase.

The number on the Crank in this case 2112221112 refers to the size of the crank bearing surfaces. The crankcase number 454645 refers to the crankcase journal seats, you may notice that the numbers are not the same length, that's because Yam added the con-rod bearing surface sizes, so as I am not touching the con-rods I can ignore the right hand side 4 numbers. So that gives me : 211222 and 454645.

In order to work out the journals to purchase you need to subtract the relevant pairs. That means :
With this you go to your favourite online shop (or local dealer) and order your journals. I have 2x2, 2x3 and 2x4 and these are colour coded to be 2 x 2 black (1WG11416-10), 2 x 3 brown (1WG11416-20) and finally 2 x 4 green (1WG11416-30).

Of course I am assuming that the original Yam sizes are what is in there and that they haven't significantly wornout. By the way, the reason I am changing this is because they are pretty much all marked up in some way, this may point to bad oil changes or significant crap in the sump which is what I found! You can go through the complete process of measuring clearances with Plastigage, but to be honest I couldn't be fussed, let's hope this was not a foolish shortcut.

Will update you when I get my bits....

Tuesday, 29 August 2017

New Piston

A bit disappointed with my new piston, it looks like it has been water damaged or something. It doesn't seem to be physically compromised, so it went in, after a good clean. The new and old pistons are physically the same - 210 grams

It went in, no problem and the rings were in perfect condition so should be OK. I broke the temperature thermocouple as it was all going back, but one from my FZR stock of parts will fit. Just need to fill up liquids tomorrow and see if it works!

Thursday, 24 August 2017

RD 350 Update

Just to make a note of the squish values, measured with the existing pistons (one cracked and the other OK).

Nothing surprising really all around 1.0mm which is appropriate for a 175cc cylinder.

Cleaned the head up and the piston (for measuring the squish), stuck the bits of solder on to the top of the pistons and then tightened down the head and rotated the engine one time to ensure the solder got squished on both sides. The cylinder and head don't look any worse for where, but this is becoming a nasty habit every couple of years, so will have to investigate a little.

Wednesday, 23 August 2017

Yamaha 350

Just back from hols. in Scotland and back to 30 degrees centigrade in the workshop! The 350 had been getting really difficult to start - only pushing it would work, so I was troubleshooting before the holiday, the left hand carb was missing the idle screw so I thought I had found it, anyway I sourced a new idle screw and it was exactly the same!

So with fuel and a spark, the next thing is compression. I pulled the generator cover to see if the left hand crank seal was blowing, and no oil in there, so I decided to remove the head, once it was off it was clear what the problem was.... The piston was cracked on the crown and all the way down to the gudgeon pin, this is potentially the 3rd time this has happened. Maybe the consequence of over revving....?

I have purchased a Mitaka replacement that I am assured is exactly the same as the cracked one, £60 from PJE motorcycle Engineering posted.

Wednesday, 26 July 2017

Daytona and RG

The new frame rails added back
After modification

The Daytona fell of it's stand! That's the second time since I've had it (11 years). The clutch lever snapped, and the front indicator pushed back into the fairing cracking it significantly. The engine cover and passenger footrest took the rest. Today I got around to seeing what could be done. I managed to superglue the fairing and clean up the other scratches with a touch up paint stick (an old one from Olly's Decathlon bike). I also touched up the black on the engine cover and rear wheel hub. All done and looks OK from a distance..... Will wait for a better fairing panel on eBay.

I finished messing with the RG frame and put things back together, lots of shag and hassle but it's back and looking better than before.

Monday, 24 July 2017

Street 20k Service

I had already changed the oil and filter at 15k, so the only thing left, was to change the air filter (a pipercross) and plugs, (you should also check the valves but that will wait a bit - this winter). The bike had passed the 20k kms and I completed the service at 20434 kms.

To get at the air box, you need to remove the tank, which pivots up once the two front allen screws are removed, you can use the provided (under the seat) prop to hold the tank up while you look at the fuses, but to get at the air box you need to remove the tank completely by removing the bolt going through the rear of the tank, and then disconnecting the 2 electrical connectors and then removing the petrol quick connector by sliding up the orange/red clip to access the two black push buttons which allow the quick release connector to come away with very little spillage (none in my case).

The top of the air box has all the electrics on it including the ECU and the fuse box, but this all flips to the left hand side once the 8 self tapping screws have been removed. In order to change the plugs you need to remvoed the airbox completely, this is held on by the 6 screws going through the throttle body bell mouths, and one screw (very tight) at the front which once loosened allows the air box to slide towards the rear, there are two pipes one front left and the other rear right, which attempt to stop the air box sliding rearwards! I also disconnected a big electrical connector situated behind the air box getting in the way.

Each coil can be disconneted and then removed (pretty stiff) by pulling, however the LHS cylinder needs some pipework moving out of the way (I think it's emmissions stuff), I also need to remove the LHS small plastic cover in order to get the spark plug socket into the hole and move the multiple cables out of the way. Replacing this piece of plastic provided some entertainment getting it to fit appropriately!

With the 3 plugs changed the re-assembley went OK, apart from the plastic panel above and routing the tank overflow pipes through to behind the swinging arm.

Tuesday, 11 July 2017

Modifying the RG frame

As you may remember I bought a second hand frame when I was getting my old one straightened. Well it wasn't a fantastic purchase as the sub frame had been altered and it wasn't at all straight, so I set about straightening it today.

I don't know if the previous owner wanted a different angle for his rear end or what, but the left hand strut had been cut and rewelded at the wrong angle, he had also removed the supporting struts from both sides, and replaced them on one side with a piece of plate, all pretty badly welded.
I cut loose the plate, and cut through the upper strut where it had been welded, I then had enough flexibility in the strut to bend it into position.

I am buying some 20x20x2 square aluminium tube which I will use to replace the diagonale struts to support the weight.

I will followup with more photos when I get the tube.