Help bring an old flat track racebike back to life!

[MrBultaco]

Due to the age of the original build, I would bet that the right side shift conversion was done by Shell Racing. You just sent him your right side case and a shift shaft and 3 weeks later you had your parts to assemble. Hoos Racing does this now. I used a TZ250 shift lever.

 

[Apexdc]

Due to the age of the original build, I would bet that the right side shift conversion was done by Shell Racing. You just sent him your right side case and a shift shaft and 3 weeks later you had your parts to assemble. Hoos Racing does this now. I used a TZ250 shift lever.

That is interesting and very possible. In spite of the bike being built in a small town in New Mexico, they used all the right stuff. Trackmaster frame, Ceriani forks, Borroni rims, etc. I got a chance to look over a 750 that Kenny Roberts and Wayne Rainey raced and a lot of the key parts were identical. The big difference is they had the very trick OU/OW72 heads.

 

[MrBultaco]

Received my copy of the American Motorcyclist magazine today...great article and pictures of your Trackmaster/Yamaha restoration.
I see that you are a member also, so I'll let you post the article.
There are 350,000 members of the AMA, maybe with this story, someone will contact you with more information.

 

[Apexdc]

Thanks for the nice words and heads up. I was waiting until the magazine was out before posting here. I hope everyone enjoys it and I really appreciate all the help in getting here!

 

[azman857]

It was the first thing I read when I got my copy. Way cool.

 

[Mailman]

Thanks for the nice words and heads up. I was waiting until the magazine was out before posting here. I hope everyone enjoys it and I really appreciate all the help in getting here!

View attachment 186110

Very nice write up, congratulations!

 

[CC1]

Some more pix. That is Joe Pearce backing it in....View attachment 113136
View attachment 113137View attachment 113138View attachment 113139View attachment 113140View attachment 113141View attachment 113142View attachment 113143View attachment 113144View attachment 113145View attachment 113146View attachment 113147View attachment 113148View attachment 113149View attachment 113150

My dad built a 750 just like that one and sold for 600 dollars when I was 17yrs old. It was a STAR frame bike. That's nice.

 

[CC1]

Ok, I reaching out for some good advice from the folks on this great forum. I've been lurking for a long time while I was figuring how my project and getting my issues organized.

Here's the tale. I grew up in Eastern New Mexico and bought an old XS650 flat track race from a high school buddy about a year and a half ago. It was raced in New Mexico, Texas and Colorado in the early seventies and raced at Pikes Peak in the 1976 Bicentennial event.

After I got it, I did a light cosmetic restoration, really more a deep cleaning as the paint and many pieces are original. I didn't get into the engine, but believed it to be sound.

Last May, I showed the bike at the Quail Lodge Motorcycle Gathering in Carmel, CA and lots of people loved the old school look of it.

Now, I am doing two things, getting it running and converting it from flat track mode to the way it was when it ran Pikes Peak. There, it used TT pipes and a front brake that I think was probably a Honda CB450 or Superhawk brake. There is a photo from 1976 showing the bike with the front brake.

My first issue is that the kickstarter had removed, as it was a race bike. As my goal is to ultimately get the bike on the street, I am trying to install a kickstarter. The engine, according to the S/N is a 1971 or XS1. I bought a kickstart mechanism on eBay and have it installed. However, the parts page illustration that I have shows one shaft with a thrust bearing and one without. The shaft came assembled with a ziptie holding a single washer. So, first question is do I need the thrust bearing or not?

Next, the clutch is obviously an early style with six plates. Should I try to upgrade to a newer basket, or just get six new plates from Mike's and keep the rest original or ???

As far as the TT pipes, I got a set with the bike that fit pretty well. they are 1.75" and about 37" long. I have some baffles that fit well for the street. Anything I should do differently there? I have seen some inserts from a couple of source that go up by the head, but wonder if I need something like that as I will be getting some restriction from the baffles.

I cleaned the Mikuni carbs and they look pretty decent. I have a Pamco ignition, but it is not fully installed yet.

Then, last, the alternator assembly was removed, but the shaft was not cut off. My plan is to just run the bike off the battery at first, until I get a feel for how much I may really end up riding it. If it is as much fun as I think it is going to be, I will want to get a charging system installed. Any suggestions on what I should use? I have to assume there were improvements over the life of the XS, but any parts will have to fit my '71 engine.

I would really appreciate any help and suggestions you can give. I think this bike is going to be a keeper and I'm loving bringing it back.

Thanks!!

View attachment 112993View attachment 112994View attachment 112995View attachment 112996View attachment 112997View attachment 112998View attachment 112999View attachment 113000View attachment 113001View attachment 113002View attachment 113003

How did it do at the Quail gathering in Carmel? Some of the finest motorcycles in the world show up there.

 

[YamadudeXS650C]

Thanks for the nice words and heads up. I was waiting until the magazine was out before posting here. I hope everyone enjoys it and I really appreciate all the help in getting here!

View attachment 186110

Very cool article! Congrats !

 

[Apexdc]

How did it do at the Quail gathering in Carmel? Some of the finest motorcycles in the world show up there.

I was really honored that they accepted Prom Queen. As you said, some of the best builders and bikes are there. We didn't trophy, but got LOTS of great comments from the people enjoying the show. It even popped up a few places online where someone posted about the show. The attached photo was from one of those.

I like to say that people who don't even like motorcycles seem to love Prom Queen! I think it is largely because she looks so much like the essence of a what we all feel is a MOTORCYCLE! No frills, just a cool bike.

Thanks again for all the support you have all given me on this path. This was a collective effort and I could not have gotten the old gal back to life without the help of XS650.com!

 

[Apexdc]

Hello everyone!

I am back with Prom Queen for a bit of advice. I was lucky enough to have Paul Dean ( ex Cycle World ) agree to take a look at the carbs on Prom Queen. He got her running great, but after a lot of thought, I have decided that the race engine is really not practical for the street. It is a 750 with very high compression, so takes a very serious kick to get her started. She fires off on the first couple of kicks, so that is not bad. But I just clicked over 77 yesterday, have had one hip replacement and am looking at another one, so kicking over a hi compression race engine is not my idea of a good time.

The starting is more of an issue as she has no alternator or flywheel. That is what helps get that snappy fast revving exhaust sound, but she is really fussy about idling. So, won't idle, hard to start is starting to not look so good.

Facing the reality that I am not going to be doing any flattracking any time soon and since Prom Queen's next life is going to be more a Cars and Coffee or show setting a lot of the time, I have decided to pull the race engine intact and build up a friendlier street engine.

My first question is motor mounts. This is a 71 engine, kick start only. If I go with a later electric start engine, do I need to make differnet motor mounts?

Next question is how hard is a stock XS650 to kick start? I am thinking not to hard, so I might be able to get by with a milder kickstart engine.

If you keep in mind that she probably weighs at least 100 pounds less than a stock bike, I think a near stock engine will be plenty. I will have good pipes, modern ignition and K&N air filters to help a bit. I will even probably keep the CV carbs.

So, does anyone have some suggestions on how to handle this path, or should I consider another one. I know I could take a lot of parts off my current engine, but I want to keep it intact "just in case".

Oh, the photos below don't show the plate mount accurately. I had it high for the CHP inspection, but have now mounted it down by the left side lower shock bolt, sort of chopper style. Looks cool and leaves the tail nice and clean.

Thanks! dc

 

[Jim]

My first question is motor mounts. This is a 71 engine, kick start only. If I go with a later electric start engine, do I need to make differnet motor mounts?

It's been done, and as I recall, was a fairly straightforward swap. I'm thinking the front mount needs a little work but that was it.
If I remember who did it, I'll put a link up here.

 

[halfmile]

Converting over to a later electric starter engine is not all that hard. I can`t tell from the pics but does your 71 motor use the bottom frame rail mount? A 1973 engine mounted the same way as a 71 but had electric start. A later model motor mounted with the lower center mount on top of the rail. You would need to know what the width of the Track Master bottom rails is? You have plenty of room for a small Lithium battery and reg/rec and related stuff under the seat.

 

[Kevin Werner]

Hello everyone!



Next question is how hard is a stock XS650 to kick start? I am thinking not to hard, so I might be able to get by with a milder kickstart engine.

I think it would be easy, when I get mine tuned properly I will let you know.

 

[toglhot]

What's with the left side case, looks like there's no alternator, was this just a run flat battery system?

 

[Apexdc]

I think it would be easy, when I get mine tuned properly I will let you know.

Thanks! If it is not that hard, I might just do a kick start only. Guys might think I am not a bad ass if I have to use electric start! On the bad ass side, I need all the help I can get!

 

[Apexdc]

Converting over to a later electric starter engine is not all that hard. I can`t tell from the pics but does your 71 motor use the bottom frame rail mount? A 1973 engine mounted the same way as a 71 but had electric start. A later model motor mounted with the lower center mount on top of the rail. You would need to know what the width of the Track Master bottom rails is? You have plenty of room for a small Lithium battery and reg/rec and related stuff under the seat.

Here are an assortment of photos. I have a lathe and mill, so it would not be a big deal to make another plate for the rear mount. On the front, I could probably also machine a single part instead of a welded one.

Looks like four mounts in the rear, two on the same plane laterally each side, and then the front two.

I already have a lithium battery as it was a total loss electrical system. I bandsawed the top off a period Yuasa battery and epoxied it on top of a Shorai of the same size. The leads on the cap are wired down behind the battery to the real battery, as well.

The ignition is modern electronics, so needs very little current. The lights are all LED and I wasn't planning on running with headlight on. That small tank is the biggest issue for range.

Thanks!

 

[Apexdc]

What's with the left side case, looks like there's no alternator, was this just a run flat battery system?

Yep, no alternator. They cut the case down to let the bike lean over more. Total loss system. More info in the post above this one.

 

[Moppo710]

Yep, no alternator. They cut the case down to let the bike lean over more. Total loss system. More info in the post above this one.

Hi David, I have just come across this whole thread and read it all the way through right from the start, over a couple of sittings and it is amazing! Such a cool bike and incredible story, so just wanted to say thanks for sharing it with us! Plenty people have already said it, but youve done a real nice job with it now too, really lovely way to bring it back to life! Really Enjoyed reading your story

 

[Apexdc]

Hi David, I have just come across this whole thread and read it all the way through right from the start, over a couple of sittings and it is amazing! Such a cool bike and incredible story, so just wanted to say thanks for sharing it with us! Plenty people have already said it, but youve done a real nice job with it now too, really lovely way to bring it back to life! Really Enjoyed reading your story

Howdy! Thanks so much!

I’m really glad you enjoyed the story. It has been so much fun bringing Prom Queen back to life. I’m off in a different project right now, but when it is finished in a few months, will start getting organized to put a street friendlier motor in her. I’m getting my second hip replacement on December 5, so I’m thinking my kickstarting days are coming to an end. Besides, the bike is now a 750 and very high compression, so not that easy to kick it through. Fortunately, it virtually starts on the first kick, but with no flywheel is a little bit reluctant to idle very well. Just going to try to find a solid engine in a salvage yard that has an electric starter and put it in. Apparently, if I get one of the earlier ones, it will bolt right in, but I have a small mill so I should be able to make alternate motor mounts , if I need to.

I have never had so much fun with a bike that I have ridden so little. The main portion of that is the enthusiasm that others seem to have as well as my own. When I get going on the engine swap, I will post some more in this great forum. Thanks again for the nice words. All the best, David.