So Close!...
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I use aluminium oxide shot blasting cabinet that works a treat on small aluminium parts, if you have the patience...
Otherwise I send things like engine cases off to be vapor blasted.
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Managed to get the early casings for £45! Engine number 654! Sweet!…
Also managed to remove & measure the clutch actuator arm bearing and get a couple ordered. Gaskets are in the post. I’ve got just about everything I need to build…Just need to strip a rear shock so I can measure the size of the various seals needed to rebuild one…
Happy daze! 🤩 …
@SpookDog I don't think the stock DTR shock is rebuildable. It's of the IFP type meaning it has an internal floating piston and the chamber behind it (right at the top of the shock body) is charged with air or nitrogen at 300+psi. Yamaha even show you exactly where to drill a 3mm hole to safely release the gas pressure before throwing it away. With those kinds of pressures it would be quite dangerous to try taking it apart IMO.
It's like this so as the shock compresses and the piston rod occupies more volume inside the damper body, the IFP moves so the overall volume of the damper doesn't change and it just compresses the nitrogen chamber. This prevents the oil from becoming aerated which would result in inconsistent and/or total loss of damping.
I just found this which shows how the IFP works, ignore the remote reservoir as the DT125R shock accomplishes all this in a single shock body as they figured that would be all 17-year-olds needed. The DT200R and most MX bikes have a remote or piggyback reservoir to increase oil volume and reduce overheating/fading during serious off-road riding. TBH I've never had an issue with a stock DTR shock so as long as there's no pitting on the shaft and no visible leaks I think you're good to go.
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@SpookDog I don't think the stock DTR shock is rebuildable. It's of the IFP type meaning it has an internal floating piston and the chamber behind it (right at the top of the shock body) is charged with air or nitrogen at 300+psi. Yamaha even show you exactly where to drill a 3mm hole to safely release the gas pressure before throwing it away. With those kinds of pressures it would be quite dangerous to try taking it apart IMO.
It's like this so as the shock compresses and the piston rod occupies more volume inside the damper body, the IFP moves so the overall volume of the damper doesn't change and it just compresses the nitrogen chamber. This prevents the oil from becoming aerated which would result in inconsistent and/or total loss of damping.
I just found this which shows how the IFP works, ignore the remote reservoir as the DT125R shock accomplishes all this in a single shock body as they figured that would be all 17-year-olds needed. The DT200R and most MX bikes have a remote or piggyback reservoir to increase oil volume and reduce overheating/fading during serious off-road riding. TBH I've never had an issue with a stock DTR shock so as long as there's no pitting on the shaft and no visible leaks I think you're good to go.
OK, that’s interesting! I knew that they weren’t ’serviceable’ but I didn’t realise they were charged with pressure in any kind of way. Probably why they have the ‘explode~explodey’ sticker on them!
I wonder how they charge them? They usually have a pfhiefer (spelling!
) valve on them don’t they?…Cheers bud!
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OK, that’s interesting! I knew that they weren’t ’serviceable’ but I didn’t realise they were charged with pressure in any kind of way. Probably why they have the ‘explode~explodey’ sticker on them!
I wonder how they charge them? They usually have a pfhiefer (spelling!) valve on them don’t they?…Cheers bud!
…Haven’t blown a head gasket in forever!! So sweet! 🤩 I’ve almost forgotten the Pain (ITA$$!) of it all 🥲
Still waiting on the #654 casings, bank holidays and wot~not Till then I’m gonna build my new (2 me) front forks, ala proagressive springs and new tyre (balanced! No more riding a jackhammer!) new (genuine!) seals and top’n’bottom bushees. Whit new 2me speedo drive…Cost me an arm & a leg to squirrel all these bits away over the last wotever but it’s almost time to play!!
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Haven’t blown a head gasket in forever!! So sweet! 🤩 I’ve almost forgotten the Pain (ITA$$!) of it all 🥲
Still waiting on the #654 casings, bank holidays and wot~not Till then I’m gonna build my new (2 me) front forks, ala proagressive springs and new tyre (balanced! No more riding a jackhammer!) new (genuine!) seals and top’n’bottom bushees. Whit new 2me speedo drive…Cost me an arm & a leg to squirrel all these bits away over the last wotever but it’s almost time to play!!
Can’t seem to get much work done at the moment, my ‘shed’ has no walls and the weather has been, meh!
I’m out of the rain but the wind is fling more crap around than a bi~polar chimpanzee …Also, I’ve just realised that I don’t have a decent head for the new engine! Does anyone have a good 3mb head that’s not being used? For a fair price? The last pristine one I had played pong with a piston ring locator pin
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Can’t seem to get much work done at the moment, my ‘shed’ has no walls and the weather has been, meh!
I’m out of the rain but the wind is fling more crap around than a bi~polar chimpanzee …Also, I’ve just realised that I don’t have a decent head for the new engine! Does anyone have a good 3mb head that’s not being used? For a fair price? The last pristine one I had played pong with a piston ring locator pin
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@SpookDog Ouch, pretty sure 3MB heads are getting hard to come by these days...
The only ones on fleBay are absolutely hanging
Bud, I know. Weird thing is the last pristine one I bought was off of fleabay! It was about £20 as well!! Before that it was the pristine 3mbp head & barrel with the entire 3wire servo & p/valve setup for £140. There are genuine sellers out there who aren’t all sheepled into the whole artificial Dtr pricing thing! It’s just time consuming to find them…
I do have a 4fu I can use, just not sure about the squish, ect…I dinged my (genuine!) fork seal putting it in yesterday 🤬 luckily I found a geezer selling 2 genuine seals for £14 last nite. I also got 2 genuine seal washers for £10 (just not sure of the point or proper placement) and indulged in a fork seal fitting tool for £12, I just hope it works better than my chipped big flathead screwdriver!
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Bud, I know. Weird thing is the last pristine one I bought was off of fleabay! It was about £20 as well!! Before that it was the pristine 3mbp head & barrel with the entire 3wire servo & p/valve setup for £140. There are genuine sellers out there who aren’t all sheepled into the whole artificial Dtr pricing thing! It’s just time consuming to find them…
I do have a 4fu I can use, just not sure about the squish, ect…I dinged my (genuine!) fork seal putting it in yesterday 🤬 luckily I found a geezer selling 2 genuine seals for £14 last nite. I also got 2 genuine seal washers for £10 (just not sure of the point or proper placement) and indulged in a fork seal fitting tool for £12, I just hope it works better than my chipped big flathead screwdriver!
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PS
I’m also looking for a left hand casing for parts. Doesn’t need to be usable or have VIN…Does everybody else balance the tyres on their bikes? All the bikes I’ve owned and ridden and I’ve never, ever had to balance the tyres! Never even though about it. Yet my dtr used to ride like a pneumatic drill and I didn’t realise it wasn’t a ‘characteristic’ 🥴 Bad enough when it’s just one doing it! Throw in the rear with the rim~lock and it’s no wonder I didn’t like going over 60mph!! Bucking Flipping Bronco**!!**
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Does everybody else balance the tyres on their bikes? All the bikes I’ve owned and ridden and I’ve never, ever had to balance the tyres! Never even though about it. Yet my dtr used to ride like a pneumatic drill and I didn’t realise it wasn’t a ‘characteristic’ 🥴 Bad enough when it’s just one doing it! Throw in the rear with the rim~lock and it’s no wonder I didn’t like going over 60mph!! Bucking Flipping Bronco**!!**
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@SpookDog I explicitly asked not to as I didn't want it to affect the aesthetics
I rarely use my bikes and I certainly don't go at any speedDid you upgrade your front master cylinder when you fitted the brembo 2pot calliper? If so what size? I’m gonna guess you used an aprilia one!
…Just trying to find out about front master cylinder sizes, mine has a 13mm which is interesting. The 13mm rear wasn’t ‘enough’ to work a 35mm front calliper when I fitted it on the rear…
I’ve found a few different nissin ones from different bikes. Triumph do a few 14mm & 5/8in ones.
There are loads that look identical to the dtr125 ones from different 125’s which can be had for £20-30 (minus the Dtr tax which would make it £60-80) in mint condition!… -
Did you upgrade your front master cylinder when you fitted the brembo 2pot calliper? If so what size? I’m gonna guess you used an aprilia one!
…Just trying to find out about front master cylinder sizes, mine has a 13mm which is interesting. The 13mm rear wasn’t ‘enough’ to work a 35mm front calliper when I fitted it on the rear…
I’ve found a few different nissin ones from different bikes. Triumph do a few 14mm & 5/8in ones.
There are loads that look identical to the dtr125 ones from different 125’s which can be had for £20-30 (minus the Dtr tax which would make it £60-80) in mint condition!… -
@SpookDog I run four pots on the front and twin pot on the rear. The front I'm using an Aprilia RSV Mille master cylinder and the rear is on the stock Nissin master cylinder.
Braking wise the thing stops on a dime!
Cheers bud, I forgot you run ally wheels…
Do you have any knowledge about anybod that could manufacture a centre ‘hat’ rotor for the front hub? I would love to get a centre bit made so you could ‘bolt’ a floating disc to it. It shouldn’t be too difficult because there’s no offset to worry about. I’ve read that they can be made from aluminium, which shouldn’t be too hard. Just some CNC work and figuring what outer disc to fit/match it to. It’d be harder to make the calliper mounting plate to fit a 2 pot calliper too it, surely?…
Any thoughts?… -
Cheers bud, I forgot you run ally wheels…
Do you have any knowledge about anybod that could manufacture a centre ‘hat’ rotor for the front hub? I would love to get a centre bit made so you could ‘bolt’ a floating disc to it. It shouldn’t be too difficult because there’s no offset to worry about. I’ve read that they can be made from aluminium, which shouldn’t be too hard. Just some CNC work and figuring what outer disc to fit/match it to. It’d be harder to make the calliper mounting plate to fit a 2 pot calliper too it, surely?…
Any thoughts?… -
How bad are rear wheel bearings to replace?…
I’ve done one before but it was nearly 35 years ago. I seem to remember lump hammer and giant screwdriver, ala chisel? I seem to remember having to depress the centre tube to allow access to the bearing from the opposite side? Any help/tips appreciated
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How bad are rear wheel bearings to replace?…
I’ve done one before but it was nearly 35 years ago. I seem to remember lump hammer and giant screwdriver, ala chisel? I seem to remember having to depress the centre tube to allow access to the bearing from the opposite side? Any help/tips appreciated
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Leaky tube makes for another night of running~repair!…
Noticed that the rear wheel bearings are a bit ‘graunchy’
No play just the odd notch 🤬 Good job I bought some when I got the bike! … -
Pipe looks good on it.
You need to get some photos of it in the light etc, preferably on the trails!
I’m not a daytime/morning person but I will oblige when the good weather finally breaks!
…Has anyone ever had a water pump seal fail? I’ve had some contamination problems with my gear oil, it’s grey and emulsified. Horrible state! The only things I can think of are the pump seal letting a small amount of liquid into the gearbox, or possibly condisation from cold damp air during the winter. Which is a stretch of the imagination
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