Re: Project: Garage Find
 

Forks. Not as easy as you might think.

The first problem was the Fork Damper Snap Ring which is a spring clip that sits on the fork damper rod. I'm not really sure what its job is, but it stops the damper rod from coming out of the stanchion without removing it. When I took the forks apart originally I was missing one of these snap rings, and unfortunately Yamaha no longer supply them. So I thought it would be a simple job of tracking one down. I tried 3 bike shops, 4 bearing suppliers, 2 faster suppliers, 1 engineers and a couple of websites. No one could supply a match. So I had a spare set of forks, I dismantled a fork just to get this snap ring out.

http://i153.photobucket.com/albums/s...ps20d38e04.jpg

So back to assembly of the forks. The first one was a complete success. The second, not so. It one of those classic things when you find something left over at the end of the job. In this case it was the oil seal washer that I forgot to put in. The washer sits above the bushes, but below the oil seal. So decided to take apart the fork again and try again. But like so many things not as simple as it might sound.

I think because the washer wasn't there, the oil seal had made it into places that you wouldn't expect. The prevented easy separation of the stanchion from the fork lower. Me and Stretchie had great fun eventually using a vice to hold the fork, me to steady the work bench and Stretchie's excessive down force to separate it.

The fork eventually separated, but I now needed a new oil seal. And the vice had taken its toll on some of the powdercoat as we didn't protect it enough. The powdercoat was touched up with silver Hammerite and again isn't very noticeable.

A week or two later new oil seals turned up and I started to rebuild the forks. Firstly I decided to pop the oil lock off of the station and inserted the damper rod through the stanchion and added a broom handle to it. Gave it a quick couple of taps and the oil lock came off. The damper rod then didn't. Bolt and light tap though the damper rod and it unseated itself revealing the now damaged fork damper snap ring. Time to disassemble the other spare fork.

Eventually I had all the fork internals that I required, touched up the powdercoat, and had new seals so could rebuild them properly. Seals and drain bolts were from Yambits. Ruffy kindly sent me a pair of Yamaha dust seals and oil seal clip from when he owned one, many thanks for them.

http://i153.photobucket.com/albums/s...psc58f7f48.jpg

Finally I could put new springs and oil in as supplied by Hagon. A set of progressive springs were added along with their oil at the correct air gap 150mm and luckily I fall in the perfect weight range for their springs. The progressives are shorter that the standard springs which made putting the fork tops on easier than usual.

http://i153.photobucket.com/albums/s...ps092225aa.jpg

Decided to go for the Hagon springs as I understand that these are better than the standard ones and are what is recommended by those racing in the YPM series and we can all have aspirations.

Re: Project: Garage Find
 

Is there no spacer that goes atop the spring?

Re: Project: Garage Find
 

No spacer supplied. I used the standard one. Only replaced the spring and the oil from standard.

Re: Project: Garage Find
 

I only ask because my Hyperpro's were longer than stock (I think) so I needed to fabricate a custom length spacer to restore the spring pre-load height. This is what was recommended in the emulator mod, but I have no idea how much you can really play around with these things.

Re: Project: Garage Find
 

Might give Hagon a call in the morning then, but I can't hear the spring moving around or anything.

Re: Project: Garage Find
 

The rear suspension and the shock linkage was the next problem I tackled. The linkage is an interesting arrangement that is a mixture of bearings and bushes. Unfortunately Yamaha don't supply the bushes any more neither do they supply the pins. All of the bearings on the linkage were seized, all of the bushes were oval, all of the pins were corroded, all off the thrust washers and oil seals had failed.

http://i153.photobucket.com/albums/s...ps46e2f6d9.jpg

It doesn't show up as well in the photos so I've just included an exploded view here.

I tried a number of bearing manufactures and none could help. The closest I got was one who took a week to tell me they were Metalastic Bush, but still I was not closer. I considered changing the linkage to the later models arrangement as I understand that its a different setup, or changing to different types of bearings, but I want to keep it original in this respect. So I spoke to an engineering company...

http://i153.photobucket.com/albums/s...ps43aeff43.jpg

South Cerney Engineering they know how to do classic cars and proper engineering and aren't afraid to touch bikes. They looked over the linkage and manufactured me a new pin and copper bearing for the front.

http://i153.photobucket.com/albums/s...ps5adafc26.jpg

Manufactured a pair of pins and Metalastic Bush for the linkage joint ordering in the material to do so.

http://i153.photobucket.com/albums/s...ps5adafc26.jpg

Polished up the rear pin and installed the new bearings and oils seals that are still available from Yamaha.

http://i153.photobucket.com/albums/s...ps13f78b78.jpg

Only one type of the thrust washer is still available but it fits both joints so I'm using that.

Re: Project: Garage Find
 

Have you been out mugging old dears again?

Re: Project: Garage Find
 

Now on to more shocking developments. The rear shock on the bike is 20 years old, I understand that after some years the gas may not be as effective as it was when it left the factory and it may have lost some of its performance. In fact when sitting on the bike originally it didn't really feel as if it was there much.

http://i153.photobucket.com/albums/s...ps83dce60e.jpg

So I started looking around for a replacement. But there was very little on offer that was at a reasonable price. I did see Hagon offer one that is used in YPM now but that didn't really speak to me so in the end I sent it off to a suspension specialist who cleaned it up and sent it back to me a few weeks later.

I wasn't happy with the now cleaned shock as it really showed up the rust on it. Luckily included in the box was another shock, a nice new one...

http://i153.photobucket.com/albums/s...ps808c8be6.jpg

Nitron didn't do a shock for the 2MA so I called them. There was some confusion over the year and model of my bike as they did do one for the 3MA. But the 3MA uses a different shock design. So they suggested that I send them the shock I have and they would make me a NTR Sport shock for my bike and weight.

So a couple of weeks later they sent me my lovely new shock and they should now be able to supply a 2MA shock easily to anyone who requires one.

http://i153.photobucket.com/albums/s...ps1ab359f2.jpg

Compared to the original I think its a great improvement.

Re: Project: Garage Find
 

those people at Nitron really are nice :-)

BTW are you going to be sticking some fairings on the TZR?

Re: Project: Garage Find
 

Yes the bike should be and will be fully faired. Unfortunately the original front fairings were lost by the previous owner so in the year or so where I did nothing with it I tracked a set down. More on that later...