s900t8v

so today I found a good 175cc reservoir to make into a boost bottle, seeing as yamaha put it on a lot of their later reed induction bikes I think it will provide a worthy improvement in throttle response and mid rpm torque. My missing boyesens were also found too so I'll be getting those in a few weeks! to install i'll have to grind out the intake in the cylinder--- it will be good to get these mods in, the bike really feels lame despite the timing etc being bang on with dial indicator. I wonder if I need 1 size larger main jet cos I went to pod air filter...... i've finished deciding on the specs for the expansion chamber, its going to be a 3 stage diffuser and 2 stage baffle, if it doesnt work I will cut and go to single stage baffle. I am also strongly considering running a center bleed for a more unique design as well as quietness and potential wider and stronger mid powerband gains, if I do i'll run a secondary adjustable rear bleeder. Ive realised that my clutch hub dampers are shot to bits (only through browsing a YS3 restoration thread,, my hub can turn about 20-30 degrees on the primary gear before it stops, it should not be like that at all! there is also slop in the rear sprocket damper which I assume cant be good for the chain or for the gearbox etc. So I will have to remove the rear wheel and just put some rubber sheeting in to bulk up the sprocket damper rubbers, I'd say they've shrunk over the years and thats why its like that, maybe that shock loading is what blew out the dampers in the clutch hub. my fuel tank is rusty and very badly sedimenting, so I wiill have to POR it, both the inline filter were clogged up just from the rust settling down... its almost like mud its that bad.

So got it road worthied which is good. Bike Is fun but man does It have no top end what so ever. No power band either as to be expected as there is no chamber. Port timing Is why it sucks at high rpm Exhaust 144 degrees Transfer 74 Intake 288. I'm going to open the exhaust out to 180 degrees. Polish the port. Open the intake to 360 and being the transfers up to 95. That should give it way more top end. Gonna cut Down the head too. Just gotta measure the squish clearance.

The grips I've seen are expensive 30-50 and none have the right colour/texture to match the seat. The shellac trick is a great way to get the colour you're after. Plus vintage cork taped bars looks epic! I don't reckon I have the equipment to cut leather into strips to wrap in a way it would look good and brown jackets but thanks for the ideas!

so I'm gonna gradually sort out the finishing cosmetics on this bike once its roadworthied - new rear shocks - paint exhaust, cylinder + head - polish up the cases and sand out scratches a bit more one thing I'm keen to do because I cant find a matching set of brown handlebar grips is get amongst the vintage bike world, I'm going to get some textured light brown cork handlebar tape and wrap my bars and then coat them in amber shellac to get the desired colour... then the final cool trick to remove the high gloss of the shellac is to gently wet rub them with steel wool to dull the finish whilst retaining most of the colour, this makes the grips look like leather! all for $20 and it looks old school!

Yeah that's what I plan to do. May add 2. The clutch steels and plates all look within spec so The remainder slip I think is just the out of spec oem springs. after shimming if that doesn't work ill buy new oem plates 5-7km on a 2 stroke? I think it'll be hot enough but you could be right

Yeah. I've come to the conclusion there is no suitable aft part for my year model so I've thrown the oem back in. I'm going to shim the used springs and throw new oem plates in. I have new steels. Screw ebc.

some photos of the bike, now ready for roadworthy! plenty of small mods I want to do (add pillion pegs, find/mount tacho, heaps of performance mods etc etc) but for now it'll be fun to commute to work on (5-7km through the city)

hey thanks foamy! so after a bunch of screwing around with this ebc clutch stuff as I said in the other thread I swapped in the original clutch with original springs after doing a bit more sanding to remove the glaze - the clutch BARELY slips anymore and I reckon it will get better with a bit of a thrash/ride...so oem all the fkn way... the problem is that before I realised this I forked out $40 for a CK2236 clutch friction plate kit that was the wrong size 3mm instead of 4mm plates despite all the ebc catalogues saying it was right - it was NOT right, and was sold the wrong clutch springs for $40 as well - CSK042 (1976-1977 DT 175) instead of CSK039 (1974-75 DT 175) despite the listing on ebay saying the CSK042s were for the 74-75 DT 175.... THEY ARE NOT! the difference/problem is that the clutch baskets + spring retainers are different for the early vs later DT 175s so the spring preloading is different - ie the CSK042s dont put enough preload on the early basket and so the clutch slips - they are weaker than the stock DT springs ... I am not able to check but I suspect the 3mm plates are for the later DT 175 clutch basket too.... The CSK039s are for early DT175 and RD350 and should be 15% stiffer but I dont have much faith in EBC anymore. anyway so a big headache and $80 later I've decided to try and palm off these two EBC components for whatever I can get for them on ebay (they are pretty much brand new) I am waiting to hear back from the sellers but dont expect much... I have also emailed EBC to ask them what their thoughts are on all this crap. in other news as you can see the bike is pretty much ready, I am just making some mounts for the rear guard which will look guady but is purely to get the bike to pass rw... I think I will paint the rear guard black as I dont want it as a stand out item. hopefully have the bike in getting roadworthied next week!

Yeah I've emailed the ebay sellers kindly to ask if there is anything they can do. The place I bought the ck series clufch plates did not list compatibility info nor did they say there is variation in ck series. So technically they did not describe the item properly and if I want to claim through ebay I should be able to. The problem is I bought the stuff in the us and my step mum brought the stuff over to save me hundreds on shipping. The clutch springs I bought were wrong too. I wasn't convinced they were right I emailed the seller and they lied and said they were 3 weeks ago (from UK) They sol me csk042. They are 76-77 dt 175 that have different clutch basket. The earlier 74-75 dt basket I have needs csk039 (same as 74-75 rd 350) this info is based off the ebc direct website so they have me the wrong ones. The ones they gave me are weaker than the originals. I way overpaid for those springs and they're the wrong ones! To be honest I'm pissed at ebc. It's a poor effort to no have clear specifications on their products or proper compatibility information. Just weak. It's a wonder they sell anything. After reading all their complaints I probably should have gone oem. But it's so pricey here in australia. Plus I like to avoid asbestos products where possible haha. Thanks for the thoughts guys. To add insult to injury somehow the tracking says my boyesen reeds were delivered but I never got them. So there goes another 40 bucks haha. That's like 120 now down the drain. 40 springs 40 clutch 40 boyesens ;( Hopefully I can sell this ebc garbage

just did write to EBC, and also to the ebayer. I have new steel plates that are 0.1mm - 0.2mm thicker than the originals, so thats not the problem... I dont want to add any used plates in thats not how its supossed to be.... I am going to throw back the OEM springs and see if the bike is any better with the used plates/discs I sanded to remove glazing/high spots with the OEM springs... I am pissed off at this shit. ALSO after reading many complaints about EBC I decided to check the springs, the free height was 34mm when new but now they've been used a little the free height is around that of the other used OEM springs... furthermore the spring coil thickness is actually less than OEM, I am going to measure them up against the OEMs and actually calculate the spring rate to see if their claim of 15% stiffer than stock rings true... if it doesnt I will again be emailing EBC about their BS....

hey guys so I bought an EBC friction plate set CK2236 ( the p/n listed for 74-75 dt 175 models - which have the same clutch setup as CT2/CT3 175s and therefore DT 125/AG 175 models of the same era... however the original plate thickness is 4mm, and the replacement EBC plate thickness is 3mm so it seems that you can get different variations of the CK2236 plate kit? I had it all installed I didnt measure the plate thickness before dumping the oil in - so I wont be returning this item which really pisses me off.. can anyone confirm this issue of there being different subsets within the CK2236 series. was so looking forward to test riding it with a working clutch. I also bought new steel plates and new EBC clutch springs.

so today made the frame loop for the seat and brazed it on, now I just have to paint and mount the rear guard!

So today got a fair bit done. New fork seals in Forks painted fork inner tubes swapped from bad forks into replacements Mounted forks New front brake shoes. - old ones were grease contaminated Aligned brake shoes Removed the tank to clean today. The process was ----- filled with aquarium rocks. shook for 20. Emptied. Refilled with degreaser and rocks. 20 mins. Emptied. Rinsed. Filled with vinegar. Left for 1 hour with shakes in between. Rinsed with more vinegar. Dried with heat gun. Flushed with fuel and then reinstalled on bike. I'm just going to add a splash of oil into the fuel every time I fill up to keep rust at bay. Cleaned fuel petcck The engine isn't leaking a drop which I'm stoked about. Not goin to use a gasket just going to go with 518 again. Fairly convinced the loud tickin is the auto lube pump so I might swap it with a spare when I replace the clutch parts hopefully this weekend. Now it's just the seat stuff (some frame work) I need to sort out and to remount the indicators and the tail light and it's ready to rock. I have been experimenting trying to quieten down the exhaust. I'm not convinced its quiet enough to pass.

you can buy the metal etch stuff from paint stores by itself for about 20 or maybe 30... if I cant get a rust converter cheaper than that I may just go crazy and POR the thing... once its done its done... I dont want to seize the bike cos of crap in the fuel blocking the mainjet...

got the bike running today, no leaks from the rebuild, but had trouble starting it so I pulled the carb and noticed an orange residue in the float bowl, which is rust... there are 2 filters on the unit but when I drained a bit of fuel into a container there was some small rust flakes... so I guess I need to POR the tank, thats just another $85 bucks... I suppose I could just use vinegar and aquarium stones to remove the loose rust and then just run it with a splash of 2 stroke oil in the fuel?

yeah i'll cut my own gasket when I put the clutch stuff in but thats a couple of weeks away. for now I just want to take it for a spin and see how everything goes.

Haha mate it's 518 anaerobic flange sealant. It's not glue. It wipes off with a razor way easier than three bond. I don't have a gasket at the moment. Yeah crazy but I want to do a quick test run

so finished rebuilding the motor with all new bearings + seals, used threebond on centre flange and then loctite 518 on the gearbox side cover. hopefully the thing doesn't leak - am leaving it empty overnight to allow the stuff to set will be doing a test ride tomorrow, my clutch parts haven't arrived yet so will have to tear the side cover at some stage to replace the plates but in the meantime I want to test the rest of the bike properly. also put new seals into my replacement fork bottoms and started painting them, will have to finish that up tomorrow to do - install front and rear brake shoes - install engine - install replacement fork tubes - mount taillight finish mounting the seat - paint rear guard then finally it will be ready for roadworthy!

so picked up my parts bike for the following few bits I need to finish off my project - clutch perch - engine - exhaust silencer - front forks I stripped down this engine which has a good mainshaft, cleaned the cases, and all the internals and popped out all the old bearings and seals. heated the case halves with a heat gun and then dropped the new bearings in. turns out my bearing guy gave me the wrong 15x22x12 bearing, its supossedly a HK1512 (those dimensions) but the OD is 20.5mm what the heck... so will have to go there tomorrow to get it sorted. engine rebuild should be done in a few days, not rebuilding the crank or replacing the piston rings as those bits are all good!

Ebay australia. From vintage strippers. They have none left but are doing a run in 3 months of higher quality units. My unit is certainly average quality.

so couldnt resist a bargain (my step mum is in US coming back) so I have been going mad ordering things from the US, getting bargains and saving on postage ordered new steel plates $34 (save 45) ordered EBC frictions $34 (save 45) ordered dt 175 reed assy + rubber intake $15! ordered boyesen reeds $28 ct 175 enduro gearset - $10 ct 175 enduro primary $ 7 the dt 175 reed is massive compared to the CT 175, so boring out the intake to fit it should provide some good gains along with the boyesen reeds, also porting the intake timing to 360 degrees should make the bottom end really exceptional... I am prob gonna add a boost bottle too as if yamaha believed in them so do I

seat arrived today, I'm not stoked with the quality but it will do.. I might be able to fix the wrinkles by either heat or pulling the vinyl and injecting glue under the vinyl... I really like the style so I forfeited a bit on the quality ... so left on my todo list - pick up the parts bike this weekend for > the engine, forks, exhaust silencer, rear mudguard, clutch lever and a few other bits. - rebuild engine (new bearings seals + clutch plates/discs) - modify the frame to support the seat (i'm going to mount seat with velcro to allow easy access to oil pump) I've chopped the rear arch which would have prevented me from mounting the seat. I'm a bit worried as roadworthy are strict on frame modifications - replace the damaged fork tube - install new rear brake shoes - replace the clutch perch which is cracked - the lever is also worn where the pivot bolt is. - install new chain cosmetics - paint the cylinder - paint replacement forks - paint the rear mudguard (will need it for roadworthy)

well i've been going crazy. I have 2 complete motors with bad mainshafts, and I plan to pick up a complete parts bike in a week or so which will give me 4 top ends, and hopefully one useable bottom end... so what I also did was pickup a CT 175 complete gearset in USA that my step mum is going to bring over for me for $10 USD which was just a crazy bargain, I also purchased a CT 175 primary gear (19 tooth) for $7 and some clutch steel plates. ideally I want a complete ct 175 geartrain (primaries + gearset) but at this stage I dont have the 74 tooth CT clutch basket. the gearing differences AG primary = 72/17 (4.3) vs CT PRIMARY 74/19 (3.89) gears CT AG 3.181 vs 3.181 2 vs 2 1.368 vs 1.368 1 vs 0.875 0.8 0.666 ag RPM drop per gear 2413 2054 2342 1553 ct rpm drop per gear 2413 2054 1749 1300 with the different primary gearing the ag bike has shorter 1st 2nd 3rd but 4th and 5th are much longer so bike can still do 100kph - you can see the 600rpm drop is fairly significant. I am hoping perhaps I can put the CT gearset in with the ag clutch basket but ct primary to get 72/19 (3.79 ratio) this will give me the shorter gear ratios but with the same top speed. I am not sure if this is possible as I dont know if the 17 tooth and 19 tooth primary gears have the same diameter/tooth width etc - if not Ill have to buy a CT 175 74 tooth clutch basket instead of the ag 72 tooth basket. if I cant be bothered doing all this I'll just take the mainshaft from the transmission and use with all the other ag bits - the gear ratios aren't that bad. if I run the CT gearset with the ag primaries as it will be super short ratio throughout with top speed of 80 (like the ATMX gearbox) - I could then run a 15t on front and 37t on back to bring it back to normal

Figured i should just do the lot. The rest of the motor will be fresh. I found a ct 175 tranny with primaries so will put that in!

Clutch is slipping despite correct width plates and new springs. Plates are warped. Dc plastics USA sells plate kits for 24 bucks. Just confirmed with them they have the cutouts so ill order some of those. Then will order ebc friction set.