Hey everyone,
I finally got some time to start my next project. My poor old racebike has been collecting dust in my office for almost 10 years now.
Its time to get it running again and make it a sunny day rider. The goal of this thread will be to entertain a few vision dudes. As well as a motivator for me to keep moving on this project. I must say at the risk of sounding like a jerk, This will not be meant as an instructional on how to do the things I end up doing. The chain drive conversion is a very expensive task. And is not something your average dude can do. If you are a machinist already I'm sure you can figure it out and I am willing to share any measurements needed. I do not have drawings and step by step instructions. Anyone interested in doing a chain conversion should just take $500 bucks and burn it! If after that your still interested, Then your certifiable!! I cannot imagine at today's machine shop prices you could have the work done for less than 1500 bucks just for the chain drive conversion. Anyway that being said I will try to address questions you have.
A little history on the bike then I'll explain what I have got started with.
Its a 82 vision motor in an Yamaha FZR400 Aluminuim chassis with 650 cc JE pistons, (the 650cc kit requires machining the cases) corrilo rods, balanced crank, Megacycle full race cams. Polished ports and Mikuni Flat slide carbs. Last time I did a dyno pull it was making around 80hp. I won lots of club races and 5 class championships in the 90's With my best year in 97 going 14 for 14 main event wins at PIR here in Portland. Nobody beat me that year in any race. The bike was untouchable!! I was racing against Honda Hawks and Kawi EX's as the SV650 was not out yet. that year I also got 2nd at a few national races and the bike ran great, Never had a motor problem in the entire time I raced it.
Anyway last time I rode it at a track day 10 years ago, the chain drive started leaking a little oil. So the first order of business is to repace all the seals and fix the leak.
If the pictures are loading?? you will see the way the chain drive system works.
There is a seal held in place by 4 bolts into the case. Then the sprocket is custom made from machining down the stock helical gear, then a outer piece was slipped over that and welded on, machined down for a seal surface. As well as a bearing on the end inside it. Then the cover piece has a post on it that goes inside the bearing/sprocket. This accepts the side load as the cases were never designed to accept this load. I know of some dudes who have done this conversion without that outer bearing but this is the way mine was done. Then that outer cover bolts to the frame as well as the motor, so it becomes part of the motor mounting system.
I have removed it all and replaced the seal. Now I just need to reinstall that stuff and it should be good.
Next I want to build a new exhaust muffler system In the last picture you will see my pipe. This is prolly the 5 or 6th exhaust I have built for this bike. This is by far the best one I built. I just am going to change the mufflers to something a little cooler looking. The header system is going to stay the same. I had a Ducati exhaust on my bench one day and saw the way they collect both the front and rear pipes into a 4 way with the pipes then coming out to each side. I decide to copy that and bingo the next race I had to drop a couple of teeth off the rear sprocket as it was way faster down the straight. With this style you really don't have to be so concerned with the length of the headers as it all comes together anyway. The small pipes are 1.25" and the larger is 1.75" diameter. I am looking into the style of mufflers now. But I like the shorty megaphones out there and will consider those.
Thats about it for now, I need to get some mufflers on order so I can finish the pipes and get those off for ceramic coating.
Next will be a 2006 GXSR upside down front fork assembly with radial brakes. I plan on fitting that maybe next week.
I'll try to keep the postings coming. If the pictures are not loading please somebody tell me how to do it.
I choose file down below, but I don't see where to add them to the post.....
Cheers!