Member Contributer tsmitty Posted April 12, 2023 Author Member Contributer Posted April 12, 2023 The right fork looks surprisingly good! The top "guide" has some gouging from dirt but just the teflon, I'm not worried, the wear will be in a different spot when reassembled. The "slider" looks amazing, it still had the .001 shim I put behind it in the early days. I haven't cleaned up and looked at the lower tube for wear but as clean as the oil was, i'm not expecting a problem there. The upper tube is bent by .016 the book says .010 is the service limit. I think I can get it much better if i could get my hands on a arbor press for a couple mins. Grrrr. Here are a couple pics Weather in Ohio is amazing! Quote
Member Contributer Captain 80s Posted April 12, 2023 Member Contributer Posted April 12, 2023 I straighten fork tubes in my press no problem too. I have a couple hard wood v-blocks and then mount the tube in my wheel stand and spin with a run-out gauge to check and mark where if more is needed. Easy as shit, pretty much like your setup. Nice. Is that your pre-load spacer? Quote
Member Contributer tsmitty Posted April 12, 2023 Author Member Contributer Posted April 12, 2023 5 hours ago, Captain 80s said: I straighten fork tubes in my press no problem too. I have a couple hard wood v-blocks and then mount the tube in my wheel stand and spin with a run-out gauge to check and mark where if more is needed. Easy as shit, pretty much like your setup. Nice. Is that your pre-load spacer? Yes lmao..! I raided my dads garage and stole his PVC... Father forgive me lol. I swear working on this thing is like opening a time capsule... Quote
Member Contributer tsmitty Posted April 12, 2023 Author Member Contributer Posted April 12, 2023 My saving grace on this project is; the guy that had the bike before my son got it, bought the bike not running and with broken carbs. He never could get it running and stored it in the back of his shop. So the bike is in pretty good condition, but let go mechanically. The guy should have looked a little closer under the carbs, he would have looked down pretty smooth in & ex ports. The pistons were weight matched and balanced with the crank and the crank was balanced to come alive between 8k - 10.5k rpm. I honestly don't know how that happens... I would think, once balanced, its balanced at all rpm's within reason of course. Anyway, i know it runs, its going to handle very well, i hope and it might look pretty good too. Quote
Member Contributer Captain 80s Posted April 12, 2023 Member Contributer Posted April 12, 2023 24 minutes ago, tsmitty said: Yes lmao..! I raided my dads garage and stole his PVC... Father forgive me lol. I swear working on this thing is like opening a time capsule... I've never seen capped spacers... I like it. Whatever works and is in the garage at the time. Quote
Member Contributer Captain 80s Posted April 12, 2023 Member Contributer Posted April 12, 2023 2 minutes ago, tsmitty said: My saving grace on this project is; the guy that had the bike before my son got it, bought the bike not running and with broken carbs. He never could get it running and stored it in the back of his shop. So the bike is in pretty good condition, but let go mechanically. The guy should have looked a little closer under the carbs, he would have looked down pretty smooth in & ex ports. The pistons were weight matched and balanced with the crank and the crank was balanced to come alive between 8k - 10.5k rpm. I honestly don't know how that happens... I would think, once balanced, its balanced at all rpm's within reason of course. Anyway, i know it runs, its going to handle very well, i hope and it might look pretty good too. My neighbor works on Triumphs a lot. He has cranks balanced for different rev ranges and usages. I think it has to do with primary and secondary balance and vibration (???). A 90 degree V-4 has perfect primary balance. Black magic whatever it is. I've only trued single cranks, let alone balance anything. Let the Pros do what they do. Quote
Member Contributer Terry Posted April 12, 2023 Member Contributer Posted April 12, 2023 Interesting spacer; you would want that to be open to the air otherwise it will behave like you have a very high oil level. Quote
Member Contributer Captain 80s Posted April 12, 2023 Member Contributer Posted April 12, 2023 4 minutes ago, Terry said: Interesting spacer; you would want that to be open to the air otherwise it will behave like you have a very high oil level. But if everything is compensated (like oil level and pre-load) to your liking... Quote
Member Contributer Terry Posted April 13, 2023 Member Contributer Posted April 13, 2023 I was made to think about this in discussions with our local suspension guru who was working on my MT-10 Ohlins forks (which I wanted softened on sharp bumps beyond what the adjusters could do). He went to the trouble of machining down the spacer to ensure that it occupied as little volume as possible, as anything that reduces the air volume over the oil causes quite a steep increase in effective spring rate as the fork is compressed. But you are quite correct that a closed tubular spacer would be OK provided the volume of fork oil was reduced to offset the volume. 1 Quote
Member Contributer tsmitty Posted April 13, 2023 Author Member Contributer Posted April 13, 2023 Oh hell I never gave it that kind of thought. I was just a wrench turner. Progressive Suspension said the stock spacers had to be shortened and I didn't want to destroy the stockers. Thanks for the fork lesson Terry, it'll take a minute to wrap my head around that. The spacers do have holes in the ends but. So aluminum tube cut to length and swiss cheese the walls? I'm all about it! I'll over think this one through Fall! lol Quote
Member Contributer DannoXYZ Posted April 13, 2023 Member Contributer Posted April 13, 2023 No need to swiss-cheese, just have open-space at ends to expose internal volume. The caps on yours is so spacer actually stops spring instead of dropping into centre and doing nothing (because pipe chosen was too small in diameter). Factory config uses wide washer in that place. Spacers don't do anything but provide a stop for spring. Lower the stop (longer spacer) the more preload spring has and this lifts front-end. Shorter spacer lets spring relax more and has less preload and lowers front-end. For example, factory spacer and spring on top of this photo. Stiffer upgrade spring on bottom has thicker and fewer coils, resulting in shorter overall length. Just need to keep overall total length same since fork is still same length. So make custom PVC spacer to result in exact same total length as stock. Softer springs have more coils and are longer. So to fit them, you need shorter spacer to give more room for spring with same overall length as stock. Basically going in opposite direction as above. 2 Quote
Member Contributer Terry Posted April 13, 2023 Member Contributer Posted April 13, 2023 Yeah, what Danno said. As long as air can pass through the spacer then all is good and no need to go the full Swiss Cheese route. Quote
Member Contributer tsmitty Posted April 13, 2023 Author Member Contributer Posted April 13, 2023 Thanks for the schooling. Can someone give me that length, I don't have the stock springs or spacers to measure from. Thanks for the input all! Quote
Member Contributer Captain 80s Posted April 13, 2023 Member Contributer Posted April 13, 2023 I've found set up instructions typically have a preload starting point of 20mm (for a proper spring rate according to your weight / usage). That's usually approximately the length of the threads on the fork cap. Oil height and preload can then be adjusted to sag numbers and preference. Obviously easier with adjustable caps, but if you have the right springs, you're usually not doing a lot of fiddling. I'm not a suspension expert by any means, but I've rebuilt and setup a lot of 80's and 90's forks. I've found with the right springs, personal preference tweaks are not likely to totally F things up. Also, I only use straight rate springs. 2 Quote
Member Contributer tsmitty Posted April 13, 2023 Author Member Contributer Posted April 13, 2023 2 hours ago, Captain 80s said: I've found set up instructions typically have a preload starting point of 20mm (for a proper spring rate according to your weight / usage). That's usually approximately the length of the threads on the fork cap. Oil height and preload can then be adjusted to sag numbers and preference. Obviously easier with adjustable caps, but if you have the right springs, you're usually not doing a lot of fiddling. I'm not a suspension expert by any means, but I've rebuilt and setup a lot of 80's and 90's forks. I've found with the right springs, personal preference tweaks are not likely to totally F things up. Also, I only use straight rate springs. Thanks Capin' , I had prob 1/2in more preload than the cap threads, but I will make that change when I assemble. I did a butt-load of sport touring/camping W.VA with the bike, that would explain the stiffer spring set up plus...I just wasn't that good, to assess and make suspension changes, at the track, there were just too many other things I was spending my attention on while i was out there. 1 1 Quote
Member Contributer Captain 80s Posted April 13, 2023 Member Contributer Posted April 13, 2023 Nice! This is "Chrissy" reloaded after camping for the weekend with the family outside of Winthrop WA at Lake Pearygin. From our campsite the night before I left. Crossed over into Canada for a week long solo trip around NE British Columbia. Had such a great ride. 4 2 Quote
Member Contributer tsmitty Posted April 14, 2023 Author Member Contributer Posted April 14, 2023 Right fork started out bent by .016 TIR now at .007 Left fork started out at .007 TIR didn't touch! Couldn't find a shop that straightens fork! So I made my own set-up... I had to flex the fork .300 in to get it to unbend! (check out the pic... 4 1 Quote
Member Contributer Captain 80s Posted April 14, 2023 Member Contributer Posted April 14, 2023 Yeah, no one will touch that shit anymore. Nice set-up in a pinch! It's kinda freaky how far you have to go to account for spring-back. Seven thou ain't shit. 1 Quote
Member Contributer tsmitty Posted April 15, 2023 Author Member Contributer Posted April 15, 2023 Fork oil; the book says use ATF, I don’t remember, thought I used fork oil, don’t remember what flavor! Any recommendations?? 🙂 Quote
Member Contributer Captain 80s Posted April 15, 2023 Member Contributer Posted April 15, 2023 They are pretty much the same type fluid. ATF (approx ~7) will provide good compliance for damper rod forks. 10 wt can slow down the compression (and rebound) a bit, but can be harsher on sharp edge bumps) I usually run 10 in my damper rod forks. Sometimes I'll make a blend of the same brand for something under 10. 15 is too high in my opinion for these type forks (without emulators). Quote
Member Contributer tsmitty Posted April 15, 2023 Author Member Contributer Posted April 15, 2023 Thanks Cap! Quote
Member Contributer tsmitty Posted April 22, 2023 Author Member Contributer Posted April 22, 2023 The fork seals are on their way! I'll be able to fit the forks together and put the front end back on the bike, then move on to the front brake calipers. While the front valve cover is wide open I might as well as check the valve clearances. Pretty sure I'll be putting dust and piston seals on the front calipers, still available I think. Is there a go-to-place to find aftermarket consumables? like brake pads, clutch kits, gaskets...etc Quote
Member Contributer tsmitty Posted April 22, 2023 Author Member Contributer Posted April 22, 2023 Quote
Member Contributer Captain 80s Posted April 22, 2023 Member Contributer Posted April 22, 2023 7 hours ago, tsmitty said: Is there a go-to-place to find aftermarket consumables? like brake pads, clutch kits, gaskets...etc I own and build a lot of bikes, so I buy a lot of shit for them. I do the majority of my shopping on ebay, used and new. I've been doing it a long time and am pretty savvy about weeding thru the junk and identifying good deals on the quality items I need (or want). Individual OEM Honda parts can be hit and miss on ebay due to shipping (like $7.99 shipping on a $2.99 seal). I have put together identical large orders and compared the final cost (including shipping) at Honda Parts sites and found Partzilla to be consistently the best deal for the types of parts I order from them (seals, orings, etc). But when you get all the way thru the order process, most of these places are pretty close to each other in the end. 1 Quote
Member Contributer tsmitty Posted April 23, 2023 Author Member Contributer Posted April 23, 2023 I admire your savvy Captain, with your full stable of rides and finding piecesparts for them all. What an awesome collection of bikes and a fantastic shop as well! I can't express how much I miss my lift, the floor work is killing me...I guess that's the "therapy" part of this thread. I don't know if I should be posting daily updates like this. Nobody's bitched yet...I don't think nobody reading this stuff anyway... While waiting for parts why not build tools! I found my valve adjusting wrench but no adjuster! So I made one... 1 1 Quote
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