mrgor Posted October 29, 2012 Report Share Posted October 29, 2012 Hello From Australia, My son has just unearthered a TL125 Sammy Miller Hi Boy Trials Bike that has been sitting much unloved for many years. A couple of days with lots of degreaser and elbow grease and the potential is obvious for our rebuild. One area concerns us in that the bike has unknown front forks. Still 31mm tubes, but they look like they may have been from a Moto Cross bike. Can we get a recommendation on what Front Forks and Triple Clamps set up will work the best in this bike? Many Thanks In Anticipation , From The Land Down Under, Peter and Ron Spencer Quote Link to comment Share on other sites More sharing options...
bigmike1961 Posted October 29, 2012 Report Share Posted October 29, 2012 I think the Hi-boy came with its own triple clamps. Oh and pics of these projects is always good. Quote Link to comment Share on other sites More sharing options...
mrgor Posted October 30, 2012 Author Report Share Posted October 30, 2012 Thank You Big Mike for your comments. If they originally came with the SM frame, they are long gone. (Frame number is 205). Unfortunately, the seller of the bike had no history on the bike, so we do not know where the triple clamps are now. Looking for some other fork set up options/alternatives from owners or those knowlegable of these bikes. Happy to send photo's, but I can not figure out how to ???? Best Regards, Ron Spencer Quote Link to comment Share on other sites More sharing options...
bigmike1961 Posted November 2, 2012 Report Share Posted November 2, 2012 (edited) As a site upporter it's easy ...otherwise paste a link to the photos in photobucket or similar. http://www.trialscentral.com/forums/topic/23551-posting-images-tutorial/ Edited November 2, 2012 by bigmike1961 Quote Link to comment Share on other sites More sharing options...
esteve Posted November 7, 2012 Report Share Posted November 7, 2012 (edited) The original (1975?) TL125 High Boy was marketed to take all the TL125 running gear so if you can find TL125 forks and yokes you will be back to standard. Look at this photo: http://3.bp.blogspot...an-horwood1.jpg - click to zoom. The TL125 bottom yoke needs to be modified to fit the High Boy frame. There are some earlier postings in the forums regarding High Boy Frames (do a search of the Honda forum). This link: http://w5.nuinternet...1/Honda_TL125S/ shows the original Sammy Miller brochure; the TL125 High Boy is on page 2 and it states that the kit price includes modification to the lower yoke. Looking at the photo of the Honda TL25 at the top of the page on this link and comparing the steering head with that in the the image of the High Boy frame it seems the modification is to shorten the stem of the lower yoke - however, if the TL125 stanchions are angled/raked wrt the stem (see my remark below) then the location of the stem in the bottom yoke will need to be adjusted commensurate with the shortening as moving the yokes closer together will require the stem to be moved forwards. Check out mid to late '70s SL100 and SL125 forks and yokes as they look the same and are the same diameter (31mm) and may be more readily available. The TL125 forks in my 2010 TL125 High Boy are 760mm from axle centre to top stanchion (just under 30") but my bike has the SM billet yokes (hence my vagueness about TL125 yokes). The part number for the SL125 top yoke is the same as the TL125 K series; 5231-110-000 - still available from CMSNL; http://www.cmsnl.com...op_53230110305/ for Euro 47.5. If the SL top yoke is the same as the TL125's then the SL bottom yoke must match dimensionally? The TL125 bottom yoke part number is 53200-355-0008; 355 infers a TL125 so that part may be unique to the TL125 but it looks the same in the parts fiche for the SL125: http://www.cmsnl.com...05.html#results - maybe the difference is something trivial like the steering lock mount? There is quite a lot of offset (from stem to stanchions) on the TL125 yokes which isn't ideal for a nice steering feel but that is what riders must have found acceptable when they were new?. I mention this as if you start mixing and matching components you could end up with very strange steering characteristics and possibly have the added aggravation of the forks fouling the tank on/near full lock if you use yokes with less offset from the stem. The SM Products billet yokes are still available and listed here: http://www.smproduct...&keyword=hi boy - I suspect they would cost more than you paid for the bike? They appear to have a large stem-stanchion offset similar to the standard TL125 items? The stanchions of my billet yokes appear to have approximately 1 or 1.5 degree offset with respect to the steering stem (does this replicate the originals?). If they are raked (its not the weather to be in the shed at night trying to measure this in torchlight) then this reduces trail. Note that the 2010 High Boy frames have slightly different geometry to the 1970's frames; the steering head angle is reduced by 1 1/2 degrees and the swinging arm lengthened by about an inch and a 1/4 to maintain the wheel base of 51 1/2 inches (according to the information on the SM webiste). There have been some "TL200" High Boys created using TLR200 engines in the 2010 frames. They appear to use SM Products High Boy billet yokes for 35mm stanchions to mount the TLR200 Forks and front wheel. TLR200 forks use a leading axle so I wonder if the SM yokes are machined parallel for the TLR200 forks or the trail would be very small with both angled yokes and a leading axle, although the standard TLR200 yokes do have a small about of rake in them. Contact Richard Jordan at Sammy Miller Products to get information and possibly find out what is required for the TL125 bottom yoke modification if you take that route. Edited December 3, 2012 by esteve Quote Link to comment Share on other sites More sharing options...
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