eric23

Time to go through the front forks. Has anyone had any luck with bearing suppliers getting the correct sized seals rather than getting the official Yamaha parts? I live in a large metro city with several good industrial supply warehouses. Thanks

I have very fond memories of my 1970 Sherpa T. They brought lightweight 2 strokes into trials to stay. However, the case for the TY80 and the mono TY's has great merit.

There is a nice write up on the Bullfrog and several other Hodaka trials specials on the Strictly Hodaka site. Jay Lael (a regular poster here) has a very nice version. BTW Sendero, I noticed there was a trail running parallel with the train tracks all the way along Rt 66. Needless to say I was totally bummed.

Other solutions I've seen out there: Membership in the club and participation in the events requires at least one "work" event. Split the group into two groups, have the riders observe each other. Our club uses this approach, the upper level riders observe the lower classes in the morning and then trade places in the afternoon.

I initially bought the TY as an inexpensive way to get back into the sport. The bike never ran that well and needed a complete overhaul. A good deal on a modern bike came along at the same time as some money came my way. I loved my modern bike until it got stolen. The thieves wanted nothing to do with the stack of TY parts, leaving me with no option at this time other than to get on with the rebuild. So now I'm back in the game with the TY175. I miss the disk brakes, hydraulic clutch and ergos of the modern bikes, and will buy one when the time is right. Meanwhile the TY is just going to have to do, and you know, being out there riding with your buddies beats the hell out of the alternatives

Our club rules state that a twinshock bike be a 1975 or later model, have twin shocks, drum brakes and air cooling. We've had some debate and disagreements over this rule, particularly as to the division between twinshock bikes and vintage bikes. I'm of the opinion that the 1975 date is a couple of years too early. There were a number of Japanesse bikes coming onto the market in that era that really are vintage bikes (my TY175 for example). There needs to be a distinction between the first generation Japanesse bikes, the earlier Bultacos, Montesas ,and MAR's, compared to the SWM's and Fantics of the 80's. I'm looking forward to reading the opinions of this post, the leadership of our club might find them enlightening.

Ringo, good to have you back around here. I can always count on some laughs when you're posting. Now if I can get our buddy Sendero to turn on his computer... For those of you who doubt Ringo's tale, believe it. There are 30-40 foot walls at Lucerne, and he is crazy enough to try anything. I've seen his bike, it obviously has been bounced off many sandstone slabs.

Been doing a lot of singletrack desert trail riding in Arizona this past winter. One of the more popular bikes out here is the Yamaha YZ250. Add a tooth to the rear sprocket, and a large capacity gas tank and they will take all the abuse that the desert can offer. I recently rebuilt my 1975 Yamaha TY175, 29 years on the origional bore and piston. Granted, it was way overdue but after some TLC, new bearings, seals and top end the bike runs like new. It's never taken more than 3 kicks; hot, cold, or flooded. Say what you like about Yamaha, but they make one tough, reliable engine, particularly the two strokes. For what it's worth, the TTR125 is very popular with the kids and wives in the desert. I've seen them being abused and thrashed yet they keep on working every weekend. I would say that Scorpa made a wise choice when they partnered with Yamaha.

I drilled holes in my airbox towards the top. Being in very dry conditions allowed me this luxury. Figured they could be duct taped up if needed. If somebody has plans or has found a better air box solution I'd sure like to see it.

We have an orange 125 here in Arizona.

I had a 2000 GG TXT280 with the timing retarded by 1mm, 3 teeth added to the rear sprocket and the slow throttle tube. Before turning it into an old man's bike for the easy lines, it had a pretty good snap right off idle. The '98 Cota just felt smooth and managable. Although I didn't open it up, the owner told me that if needed, there was plenty of power. We'll have to see what's available when the time comes to buy.

I recently got a test ride on a 1998 Cota 315. I liked the soft power delivery right off idle and the feel of the engine. I heard that Montesa went to a "snappier" engine in 2000 or so. Just trying to get an idea of how the Cota has evolved over the years.

Just going through the same myself. First off run your pre mix a bit rich ie 40:1 instead of my usual 50:1 for the first tank. Make sure that you warm the bike up at idle thoroughly before riding. Avoid high revs. I always take it out on some dirt roads or lanes for a nice easy cruise.

I installed Sammy Miller pegs on my TY175. Although they are back and down from the stock position, I still feel they should be a bit lower. I've got a local welder/fabricator lined up for the work and will report when it's all done. Fortunately the 175 pegs are attached via a bolt on plate. I can definately vouch for a wide peg like the Hebos or the Sammy Miller's, the only way to go.

You didn't mention where you're located, however I'd visit all of the bike shops in your area and find the best brand of synthetic, racing 2 stroke pre mix oil that is available at all of the shops and go with it. In my town, BelRay and Maxim products fit that test. GasGas recommends 80:1, worked well for me.

Have always had a soft spot in the old ticker for thumpers

While waiting for my trials bike to get going, I've been doing lots of enduro style riding. One of the ladies in our riding group has a TTR125. After a pretty nasty spill at the bottom of a deep ravine, I rode her bike out. That 125 engine in stock/trail form has lots of low end and decieving power. It was an eye-opener for me; a test ride on the Scorpa is in my future. A bunch of the kids in our circle ride TTR125's too, they take abuse.

The only real drawback to the TY175 IMO is the footpeg placement. Back in the '70's, Yamaha's design engineers just didn't get it right. After riding the GG for over a year, the TY just doesn't feel right ergonomicly. Fortunatly the pegs are mounted on seperate, bolt-on plates, so the solution is relatively easy to correct. You're right, an old guy like me riding the novice line will be just fine on the old bike.

Ok, the bike is back together and running very good. The biggest difference I can feel is the high position of the footpegs when compared to the GasGas. I'm bent over and the CG feels very high. After studying several photos of different trials bikes it seems that the most successful models have the pegs positioned along a line connecting the axels. I'm seriously considering building new peg mounting plates to lower them (and lower the brake peddle). Has anybody else done this? Results? BTW these are the Sammy Miller pegs.

Picked up the rebuilt engine for the TY175 Friday evening. Got it installed and running by Saturday afternoon. We've got a CAT trials scheduled for Feb 8th, so I've got one weekend to get some practice in. Sure feels good to be riding a trials bike again, even if it is an older machine.

I installed Boyesen reeds. My main concern was to avoid sucking the stock stainless units and causing many many $$$ of damage. I also fabricated a 1/4" spacer from aluminum sheeting. It worked fine, however the engine also showed signs of extreme wear in other areas. The engine rebuild is in the final stages and I hope to be up and running in a week or so. I too have the Sammy Miller footpegs, very good investment, however they could still be about an inch lower for my tastes. I also picked up some used handlebar clamps to use as a riser/spacer to raise the handlebars to a more comfortable level for me. With the footpegs being a bit high I felt bent over all the time. I bought my bike with a set of Betor shocks installed. I'm sure they're superior to the stock units although they needed to be rebuilt. I fitted new o rings and replaced the fluid, will have to see when the bike is up and running. If the TY becomes my perminant trials machine, a set of Falcons from B&J will be one of the first items to be purchased. Then a Sammy Miller tank seat unit to replace the ugly dented up stock tank. My bike was also fitted with the IRC tire. I would say that the single most effective mod would be to fit a modern tire to the bike, there is no comparison between today's modern tire technolgy and that of year's past.

While waiting for my Yamaha trials bike to be rebuilt, I've spent the last couple of months riding my Kawasaki KLX300 on singletrack enduro trails in the deserts of Arizona. The low end torque is amazing. I can find traction (sometimes too much) without losing the powerband. Although the engine braking is fine for trail/fun riding I can see where it would be a liabilty for trials work. You do feel the added weight at the end of the day, but the KLX carries it low, as would a properly designed trials frame. I'd like to test a modern 4 stroke trials machine. I've ridden a couple of vintage Hondas and the engine braking was too severe for my taste in the sections. However on the trails, thumpers are a blast.

Dan, I appaud you for taking the time to write such a well thought out reply. I couldn't agree with you more. Your advice and admonitons are the result of experience and being in the trenches. Thanks.

In my neck of the woods we call the beer soused riders on their quads "squids" . They have been the sole reason for having several prime riding areas closed for all off-road use. On the few good singletrack areas we have left, quads quickly turn them into whooped out dirt roads. For some reason or another (faulty genetics?), their idea of a good time is to ride in one continuous circle around their truck for hours at a time making lots of noise and kicking up tons of dust. Of course they park their trucks only yards from some housing development. The sad part of course is that it they only took the initiative to look beyond the parking area, they would find miles of prime trails, out of sight and out of mind from the general public. As mentioned in the above posts, those things seem to have a knack for landing on their fallen riders and causing serious injuries. Naturally, whenever some poor soul (no doubt under the influence, not wearing a helmet, going way too fast for their ability) gets killed, off road motorcyclists get lumped in the statistics. Sorry for the rant, but the day that quad riders try to ride trials, I'll go back to fly fishing.

Hey Alan, hope this has been a very nice holiday season for you and the family. The general rule of thumb for race sag is 30% of the total travel. This is for MX and trail riding, but it ought to be a good starting point for trials bikes as well. I thought it worked out closer to 2" on a trials bike. When my GG was set at 3" it didn't turn that well. Tightening it up to 2.5" brought it back in balance with the front, and the steering improved dramaticly. I'd have her do several full lock figure 8's in the driveway with 3", 2.5" and 2" and see which one she prefers.