Never ending Ace trials project

[mac]

I am determined to finally get this project finished. I have talked to Bruce Young and Hodaka Dave last week for advice/help and they are both super nice guys and very helpful.
I do have a few questions for those of you that have built one. I,m using a 62 tooth rear sprocket.
What is a good size front sprocket ?
What after market fenders work ?
Are there any decent rear trials tires in the 3.00 or so range so I could just use the stock fenders ?
Thanks !

[bobwhitman]

They’re really are no serious trials tires except 4:00x18.

[mac]

Thanks Bob.
I kind of knew that would be the case,but was hoping that maybe someone had tried something like these and would chime in saying they where decent.

[Bruce Young]

Mac, before retiring, from the motorcycle industry, I sold the Shinko tires from, Western Power Sports to a lot of vintage riders, all had very positive comments about this tire. Worth a try, not to badly priced as well. I know you are using tires for a trials bike, and should have not so much mileage or street handling, but grip, I might also suggest the Michelin line of tires as well little more wide spread of tread and makeup of tires available. Good Luck. Bruce Young

[Joe Ormonde]

I buy CHEAP and cross my fingers! A GREAT tire in a year from now may not be. The shortest lived tire I bought was a PRICEY Trelleborg that I mounted on my Super Rat around 1975. The Cheng Shin tires lasted 2X longer and were half the price. My brother bought a pair of Golden Boy Tires for his Honda Trail 90 and I mounted them with my bare hands dry. I would go with the Shinko tires. You can get a pair for around $75.00. People say you get what you pay for BUT concerning tires that usually doesn`t hold true for me! Joe.

[Bruce Young]

Mac and Joe good ideas, I might point out that most of the Shinko tire line are a fresher tire when then reach the US. And very good or easy to mount. Bruce

[mac]

Thanks Bruce and Joe,

Here are a few pics of where I,m at right now. It should have been finished long ago,but I lost my best buddy and motorcycle mentor over a year ago and it really took the wind out of my dirt bike sails. I really didn’t do much of anything dirt bike related until this past fall when I did the ISDT RR.

[viclioce]

I have used the Shinko SR241 series on several bikes! I was told Shinko bought the Yokahama molds when they went out of business. Available in 17”, 18” & 19”. I think I bought a different model for the 21” on the Wombat. Victor

[mac]

Thanks for the input and pics Victor.They show the tread much better than any online photos.

[Bullfrog]

It looks like your intent is to build a "real" trials bike. If that is the case, you should definitely install genuine competition trials tires. Any other type of trials tire will leave you spinning on wet rocks or muddy roots that other riders "tractioned" over with their competition trials tires. It is hard to comprehend the difference in "gription" between a run-of-the-mill trials universal tire and a true competition trials tire. (My 2 cents.)
Ed

[viclioce]

True Ed. But they are getting harder to find in 17” & 19”. Victor

[mac]

Thanks Ed. Other than the one used Michelin that’s on the Ace now I have always used IRC comp trials tires so I don,t know how not sticky the universal type tires would be. The IRC TR11,s are super soft.

[hodakamax]

Mac, good to hear from you. You are as bad about dragging out projects as I. Keep us posted! Maxie

[mac]

Hi Max,good to hear from you. Yes I,m a professional foot dragger lol. I was reading on your 2 the Max project and wow ! Very nice work and fun to read. I really liked all the post about aviation and model building. You have built some really nice ones and I really like the Me 262. I now have an idea on how to do the camo on my Macchi 202.
I will add more post as the Ace trials project progresses. After talking with Hodaka Dave it,s going to take a couple steps backwards because I,m going to pull the motor and rebuild the bottom end to ensure that I don,t ruin the new top end and also to make sure it runs as good as it was designed to.

Cheers!

[mac]

Having some troubles with the forks that I had on the Ace trials project. The ones that were on it are pretty pitted so I put the ones from my wombat on only to find out one is 7/8” longer than the other.
The shorter one is the same length as the stock Ace forks so I,m assuming one is from an Ace and the longer one belongs to the Wombat.The thing is that the fork from the Wombat that is the same length as the Ace forks is different at the bottom where the axle goes through. To top that off,I have another set of Ace forks that I bought that are the same on the bottom as the two from the Wombat.Those have no springs in them and when extend them out all the way the are 3/4” longer than the longest fork from the Wombat.
So,after that long confusing rambling,are the later model Ace forks different where the axle goes through than earlier models ? My frame tag says January 1970. The Wombat forks are on the left,stock pair on the right.

[mac]

Learned a little bit from watching a Socalhodaka YouTube video titled “Know what you got” about forks. Thanks Kelly ! Also from looking at fork tubes on at Hodaka Parts inc. I found that the 92B+and 94 use the same fork tubes so I,m guessing that my older Ace came with different shorter tubes.
Like Kelly basically said in the video,with bikes this old who knows what’s been changed over the years and you can,t always be sure what’s what.

[BrianZ]

The shorter lower tubes are from a Super Combat or later.

Brian

[mac]

Thanks Brian. I,ve been looking over schematics and comparing part numbers between the 94,92B+,92 and 90.
The forks on my earlier 92 seem to be a transitional mix of parts. The lower fork sliders (outer tubes) are like an Ace 90 in that the damper rods do not have an Allen bolt holding them in from the bottom. As per socals video I,m assuming they are welded to the outer tubes. The schematics show those type of outer tubes to use external springs,but mine have internal springs like the later B+ Ace.
Interesting and fun researching. I still have more to do because I want to use the wombat 21” wheel so I think I will need to use the later outer tubes. I need to get a strap wrench so I can strip them all down and use the best inner fork tubes that I have.

[viclioce]

Do you want another set of Ace forks to rebuild? I know a guy who has a bucket full, or at least he did the last time I was there! Victor

[mac]

I might Victor. I will let you know after I get everything apart and assessed. I think one of the better of the tubes is bent and I,m going to try and straighten it...we shall see how successful I am lol. Thank you !

[mac]

Another two steps back. I planned on taking it back apart to rebuild the bottom end,but decided to start it for the first time today just for an assecement of carb and homade exhaust. It ran and didn’t sound to bad,but has an air leak somewhere. The exhaust had a good sound and is pretty quiet.
The kick start did not work too good and would not catch ever time so I decided to start there tear down tonight. Did not get too far along,but far enough to find this.

[matt glascock]

Did I rebuild that motor for you at some point?

[mac]

Lol Matt. I not to familiar with these motors yet so I had to have a look at the parts schematic to see what exactly that nut was connected to that sheared off and as all of you probably know it,s the flippin main shaft that broke...ouch!
Any ideas what could cause that ? I would think that it should have made a heck of a racket when it was running,but it didn’t.

[matt glascock]

It is the main shaft nut and spring washer that used to hold the primary gear to the main shaft. The lock washer looks to be still on the shaft. I can't imagine the running motor didn't sound like a giant metal maraca. Do you see the broken end of the main shaft laying about? The good news is that main shafts are not too hard to come by. Sorry to see the set back, but it sounds like you were planning on rebuilding the bottom end anyway. Your experience brings up an interesting point. If you are beginning a project with a motor of unknown history, its somewhat risky to fire the motor - tempting though it may be to do so. I learned this lesson the hard way and ended up generating some pretty spendy internal mischief in a DS motor. Onward!

[rlkarren]

I'm just getting around to reading this thread and wanted to comment on the forks that mac mentioned.

The forks on the right, in the photo above, are the infamous "butter forks" that came on the early Super Rat and Ace 100B. They were found to be defective because they would bend too easily. They can be identified by the large fork tube nut on top and the stationary damper rod in the fork lowers. They were replaced with the forks used on the Ace 100B+, Wombat, and later. Lowers look the same but are not interchangeable, as you noticed.

$0.02

Roger