Ftwelder

I had a few very productive hours and got the seat pan done. Also held down with a Dzus fastener. It's a little lumpy but perfectly suitable for the application. I used 1.5 mm for seat and side panels so they are very light. I took a lot of photos. Now that the big things are done I can clean up my work bench and assemble the engine. Untitled by barnstormerbikes, on Flickr Untitled by barnstormerbikes, on Flickr Untitled by barnstormerbikes, on Flickr Untitled by barnstormerbikes, on Flickr

Welcome aboard. Trials skills will greatly improve your offroad skills in general and trials bikes are very light in comparison and injuries are typically less severe. Congrats on your win! Colorado has a huge trials scene so you should be able to find new areas and training partners to increase the fun factor but don't forget to spend time in the front yard practicing tight turns which is the key to good scores. Cheers.

So I got the TS250 flywheel and it's the same as the original (but nicer) so I found one for a '74 RL250 and made the purchase. It's definitely thicker/bigger. The magnets look a little different so Ill tune the bike with the TS250 unit which is in much better condition than the original 185 flywheel. Untitled by barnstormerbikes, on Flickr Untitled by barnstormerbikes, on Flickr I built the bits to attach the right side cover and put my new NJB shocks on for a test fit. Untitled by barnstormerbikes, on Flickr I started hammering a piece of sheet for the seat base and like the look so far. by barnstormerbikes, on Flickr Untitled by barnstormerbikes, on Flickr

I found one on the auction site, it's on the way!

Thanks again for following along. I mounted the pipe and it was a little "proud" from the frame rails so I squeezed it in the press to be able to fit a cover on. My original plan was do this quickly on a budget, I then went a little deep (time wise) on the fuel tank and the pipe pays the price! Haha. The cover is made so that is good. Normally the Suzuki has a shoulder bolt welded in the frame for the shock mount. I cut off the stud and made them into sex nuts. (if this isn't flagged it will be a miracle) which as you know makes bike narrower. When I did that, I tapped all the way through to use as needed. That is what the bracket is anchored to. Untitled by barnstormerbikes, on Flickr Untitled by barnstormerbikes, on Flickr We are caught up and things will go a bit slower. The good news is I have NJB trial ultimate shocks delivering next week. I hope to have the motor together in a couple weeks. Cheers. Seat base is next.

I think I read that the TS250 motor was over 10kilos heavier than the 125 based 185 so I agree that is a good choice if it will fit. Yes, my plan is to delete the oil injection system and use premix. I hope to be able to provide a funnel from the transfer port to the right side bearing and delete the deflector on the crank. The left side is fuel lubed like normal. I hope it works out.

I wanted smooth side panels and looked forward to making them. My early air box attempts were not very good so I copied the OSSA filter housing and started by making the left side panel. Untitled by barnstormerbikes, on Flickr I made the air filter housing from two pieces. First was a foam block shaped to fit the inside of the left side cover and the second was cast on the inside of a silicon reducer elbow. I made a ton of mistakes but learned quite a bit. Untitled by barnstormerbikes, on Flickr Untitled by barnstormerbikes, on Flickr Untitled by barnstormerbikes, on Flickr Untitled by barnstormerbikes, on Flickr Untitled by barnstormerbikes, on Flickr

I saw photos of either a Bultaco or Montesa exhaust as you describe and I should be able add some disruptive features in mine as needed as the main section slips on. I have room to bond a weight ring on the existing flywheel but haven't done anything about it yet. I am quite lucky to live in an area with big machines laying around everywhere and cheap commercial space so I have a lot of both. My clothing is tattered and the car is junk so it's all a trade!

I am pretty new at this (first season) and arrive a couple hours early so I can ride a casual preview loop (not entering sections) The 10:30 is probably the riders meeting with the contest starting at 11:00. We usually end at 3:00 with 30 min grace period. Time penalty after that. The first loop takes about half your time then you have to hustle to make the time limit. I carry snacks and stop after second loop for a very quick lunch and carry water on my back. My usual concern is eating/drinking enough before the event. Once the event is completed I indiscriminately eat everything in sight. 62 years, 11.8 stone. Best of luck! I didn't notice locals had given more relevant info below and mentioned different local customs that what we have here. Listen to them.

THANKS FOLKS! I like how cheap and plentiful the parts are. I have all bearings and seals for the inside of engine. Agreed on the OKO I have one on my OSSA and get on pretty well. I found a port map on line and when comparing found that my exhaust port is 2mm taller so it's possible there is a barrel with a lower state-of-tune that was also reed induction. I did as much research as I could before tampering with the frame and came up with a geometry I wanted to try and to do so would need to also change fork offset. I have some RL forks as well as the stock ones but found neither suitable so I went with Honda crowns (CNC units from WC machine) and Sherpa Betor forks. I noticed the original head tube bores were destroyed from lack of maintenance so I reamed the nominal bore in the head tube to 34.9mm and made an arbor with a facing mill and milled the cups from the end of the head tube. Untitled by barnstormerbikes, on Flickr Untitled by barnstormerbikes, on Flickr Untitled by barnstormerbikes, on Flickr I made some new cups that fit 14mm tall tapered bearings and pressed them into the 34.9 bore and TIG welded them in. I somehow managed to make the bearing fit loose (poor QC is my guess) on the upper cup but we have chemicals to make that problem go away. Next thing on the list was to compete the fuel tank. I had a lot of fun hammering out the first side but it took a lot to get it smooth. My shop makes bicycles so the gas cap thread is the same as the non drive side of a bicycle bottom bracket shell! 1.37X24 BSA. Untitled by barnstormerbikes, on Flickr Untitled by barnstormerbikes, on Flickr Untitled by barnstormerbikes, on Flickr Untitled by barnstormerbikes, on Flickr Next thing was to build an exhaust. I have software for designing expansion chambers but none of that really applies. I purchased some stainless bends in the same diameter as the original head pipe and constructed a long head pipe then made a box with a steep baffle cone thinking this may be a good start point. Untitled by barnstormerbikes, on Flickr Untitled by barnstormerbikes, on Flickr Untitled by barnstormerbikes, on Flickr Thanks for looking.

I saw this junk bike in a local ad (as mentioned in another post) and thought it would be fun to have something besides my OSSA to ride twin shock. It was $120. 119179364_3280092998770353_632717131603431554_n by barnstormerbikes, on Flickr I have a 1984 KX 250 rear wheel, KDX drum front wheel, TLR triple clamps Sherpa Betor forks and a well equipped welding shop. I am mostly modifying parts and cutting a few corners to get it done in case things need changing Ill post up a bunch of photos tonight and more in the next couple days and I hope you find it interesting. Motor looks nice. I know it's rusted solid so I have very low expectations. DS185 by barnstormerbikes, on Flickr I had already made half of the fuel tank learning my English wheel and it looked enough like Suzuki for me to choose this bike. I built up my wheels and measured the original frame. Ended up reducing the head angle by 10*. seen in this photo with stock forks and lowered shock mounts. I should have increased the rate of shock progression by angling the shocks more. Untitled by barnstormerbikes, on Flickr I lowered the seat tubes more. Untitled by barnstormerbikes, on Flickr 6.2 thick T6 6061. Untitled by barnstormerbikes, on Flickr Untitled by barnstormerbikes, on Flickr Some end work. More later, thanks for looking. Untitled by barnstormerbikes, on Flickr

Great thread. I tried TIG welding a stainless barrel to a cable and got no where.

I found one of these locally for low money and thought the same thing. Perhaps machining a bit off the bottom of the cylinder and the right pipe might bring it around. They are light and narrow with decent brakes.

Thanks for the advice and kind words, I have a friend who had a C15T in stock form and strongly suggested I avoid the wide ratio box. Over here events are generally held on a single piece of property so not much need for a tall gear besides being rare and expensive. I do agree about the chain line and swing arm pivot relation. I cycled the suspension with a spring in place of several links of chain (with a 16T gearbox sprocket) and at ride height had no swing arm contact and may be 10mm chain growth. Food for thought... It might be nice to sub in the close ratio Victor first gear which is a taller so first and second are closer and then select the smallest gearbox sprocket that gives good chain line at ride height, use the rear sprocket to make things work.

As I inch closer to being half way done assembling my motor, I need to decide what to use for a gearbox sprocket. I have a 18T crank sprocket and a 52 on my rear wheel. Standard SS ratios in a dedicated trials machine. My local suppler (bsaunitsingles) has suggested a 13T as a good starting point but there is also a 12T available. I ran out of "meaningful" progress while waiting for parts to I took the case covers to the polishing wheel. Ill never do that again but it sure looks nice.

I am 62 and just started a couple months ago. Ride every chance you get, even in circles in the door yard and build balance and core strength. Major fun!

I finished installation and it started first kick. I tried using the stock rubber spacer with the adapter spigot supplied and had a big air leak once the bike warmed up. I righted that and adjusted the idle circuit. It's very close to perfect. Ill raise the needle a little tomorrow and see if the acceleration can be improved. I like it so far.

Months ago I bought a random 26mm OKO off ebay to use as a mock-up for my BSA and it ended up being legit. My new one should arrive tomorrow so Ill compare the internals myself.

It seems I only need to shorten the throttle cable housing 17mm and it should bolt right on!

My original IRZ is working just fine and with very low miles I decided to try replace it before wearing it out further. I purchased a Taiwan made OKO kit from Mid-Atlantic trials (I am in the states) and wonder if any of you had gone this route? The tuning seems straight-forward.

The motor, clutch and fit/feel is perfect. I could balance without moving, do simple roll-backs and turn with the forks against the stop but It had no brakes (even with all new parts). This afternoon I fixed the fork leak and ground a ton of rust from the front brake drum liner which seemed to be a big improvement. It's got tons of compression, starts first kick, runs cool and the plug reads perfect. It pinged once when I almost stalled setting the slide stop and doesn't smoke. It seems perfect. I need help more help than the bike does at this point.

My 1972 MAR barn find with super low miles (770) . I took off the fragile bits and replaced them along with filling the holes in the tank and lining with epoxy. I rode it today for the first time Rare find in these parts by barnstormerbikes, on Flickr Untitled by barnstormerbikes, on Flickr

Last night I had laid the bike on it's side in preparation to remove the petcock and carburetor this morning. Upon arrival, I decided to move the bike to another spot and when I stood it up, started flowing gas! I pushed it to the embankment and it fired right up! I did a quick plug reading, jetting seemed fine so I went back, worked on the throttle to remove the slack and took her out for a spin. Other than having no brakes it works really well. It idled down low and the clutch seemed amazing. It started several times with a single kick, throttle closed. g I think I figured out where I went wrong on the fork work. I missed the seal between the damping rod and bottom cone. Thanks for looking. Untitled by barnstormerbikes, on Flickr Untitled by barnstormerbikes, on Flickr Untitled by barnstormerbikes, on Flickr

Thanks for that tip, it worked well. I used a 12mm carbide burr with a ball end so I could chamfer the edges of the cuts while I was as it. I made good progress today and got it fully assembled but more work is needed. When I was changing the throttle and cable I broke the adjuster boss off the top of the carb. I made a work around with epoxy but have a littler throttle cable play and no adjustment. I also have a persistent fork oil leak., I replaced O-rings at the bottom and even installed a gasket under the bolt head but left side is still leaking. What I hope is the final obstacle is the fuel petcock is clogged and no fuel is flowing. I only put a liter or so in the tank so I can lay the machine on it on it's side and remove the petcock and hopefully restore it without spilling gas. I need to have it running by 7:00 AM to make it to the event on time. The tank had holes and was deformed from ethanol fuel and/or crash damage to is will be ugly for a while. I used the Kaswell kit and adding fiberglass to the outside. Untitled by barnstormerbikes, on Flickr Untitled by barnstormerbikes, on Flickr There are other things but I am done for today,.