DT125R FORUM

I've never had any luck with the Chinese ones winner racing. I say that but the ones I bought for my ETX were from them and they actually fit, sort of.

But I have bought numerous previous one to no avail.

It's looking smart with that pipe on it.

The usual suspect for running hot can be the thermostat.

I must admit, DTs always seem to run hot, I tried all sorts (including twin radiators) and the solution for me was to remove the thermostat.

This is really not ideal as the thermostat is an integral part of the engines cooling, it applies pressure to the cylinder head and prevents hot spots from forming.

But I found the DT was just running too hot and would benefit from a lower temperature thermostat (especially if tuned).

But as they say Mr Yamaha know what they're doing and it's a tried and tested machine

Oh hey blast from the past!

Yeah @HOTSHOT-III is still knocking about.

Sorry to hear about your health problems, considering how much you use your DT that's a crying shame.

Good, sounds like you've ruled out those two main issues, so it'll be something simple. Radiator cap is a usual suspect.

Okay, good, using a good gasket set and the head/skim means it's unlikely to be that.

But yes, the headgasket only goes on one way.

You should be able to read UP on the gasket as it's installed. Otherwise you've installed it upside down.

Let's assume you haven't done that and it's all installed correctly, then I'd still be looking at the overflow bottle. It's possible that your radiator cap is shot and it's not hold 1.3 bar of pressure anymore and just overflowing.

The kickstand, or are you talking about the coolant overflow pipes that should be routed through the holders next to the shock absorber to the flow.

This is usually an indication of head gasket failure.

When you rebuilt the top end, did you skim the head like I describe: https://dt125r.co.uk/topic/11/how-to-i-gentle-skim-your-head-barrel

Did you ensure to use genuine/Athena head gasket?

Do not use those cheap white head gaskets they don't work.

Also did you fit the gasket the right way around.

If you stick your fingers into the top of the radiator, are your fingers black/oily?

Okay...so some overnight parts from Japan and CMSNL and some others from Australia I've finished the gearbox rebuild.....

Brand new genuine output shaft from Japan and a brand new genuine 3rd gear....

This completes the output shaft rebuild.

New genuine shims, circlips and bearings.

Fingers cross that's all back together correctly, I'll have to remember to select all gears and test BEFORE firing up the motor, else this will be £8000 down the drain if it destroys the motor.

And whilst picking the shock spring up from the paints for my ETX, I also picked up the swinging arm for this bike too.

Should go without saying, all near bearings and a lovely carbon fibre chain guard which I bought about 5 years ago for the Raptor. I'll probably keep the Raptor bone stock and therefore it's not needed for that project and can go onto this beasty.

I did have some swinging arm spool spacers machined up but for the life of me I simply cannot find what I done with them. No doubt they'll turn up eventually.

@HOTSHOT-III No, I believe it's a Yamaha DT230 Lanza arm. But yes it's like half the weight of the original one I had. I just need to get the right parts machined up to fit my wheels etc. I've been so spent on 4/5 other very expensive projects that I just haven't bit the bullet yet to order the machine shop work.

With regards to mudflap where, I'll probably design some sacrificial item in CAD and 3D print it.

@RikuRo I've sent you various links. Any DTR from 1989-2004 will do.

https://dt125r.co.uk/topic/13/kick-start-conversion-dtre

@somerandomguy314 Really? I am sure that's not the case, I sell to EU all the time through eBay's Global Shipping Programme.

Ask the seller if they'd enable it, it's invisible to them and they just ship it to a UK Warehouse.

Yeah they look fine to me.

These should also be fine:
https://www.ebay.co.uk/itm/116279866645?_skw=Yamaha+DT+125+RE+crankcases&itmmeta=01JX03X6VVAFP9E9Z1NP9SY87B&hash=item1b12d1f515:g:H40AAOSwUhhmsOr2&itmprp=enc%3AAQAKAAABAFkggFvd1GGDu0w3yXCmi1djPRfESolzX71X2HK7hTM%2FDj%2BoDtwCh8%2FDaTbV25VtpKT%2FvoiBAhKUPCoV9o7%2BrJIBiSJlTxhSY8Iw%2B5lccle4P0X8%2FfisbWP1L79DbaKKTNEwnqIVHrI0bJOnz7%2B1c9KfWOEFAS7423SjY3PVICjkN%2FrkYG6LtNPjcLeWQljy7Ea%2Bm%2BxMxUasDWHlcyQHLDcPiLxwdaDtyRQYQz6n2x8dnaESbYvxsURxwy0wU%2FVWL%2BJgeoH2Zs6Cs25%2ByAD68n%2BylpKgp7hl9L8h85cD8ciPiIuoZNQToGjcICIAGrmA9oFAlHsyf3ZBNNEIwZObous%3D|tkp%3ABk9SR5Du9IPoZQ

And it's £88 already in the UK.

It's been a while since I've looked at DTRE cases, but these look like they'd fit.

YAY!

What has been, three long years and the bike is finally on its own two wheels again.

Trip down to the powdercoaters to pick up the suspension spring as it just didn't feel right to put the crusty one on there.

I had it repainted the OEM colour for this bike, but fitted the RX/MX/SX shock absorber. It was refurbished to the best of my abilities.

Sadly the bike isn't concourse and never will be.

But it's starting to come together nicely now!

And at least I can move it around the garage out the way of the other bikes finally!

I must admit, I don't recognise that part.

Have you located it in the parts diagram?

Not a good weekend for projects sadly.

Today felt like a good time to tackle the the gearbox rebuild.

Input shaft stripped ready to lay the gears onto the 1st gear conversion.

All rebuild, new bearings, shims and circlips.

So far, so successful.

Next tackling the output shaft.

Was going extremely well...until it came to dismantle third.

This was not coming off and the prognosis wasn't good. Rough running third gear with swarf coming out of it.

The layshaft's damaged beyond repair and so was third gear.

Luckily the layshafts can be had brand new and I managed to find third gear.

So sadly that's the cost of a used gearbox, but then that tells me for scrimping on the gearbox.

The layshaft's coming from Japan so I'll have to park this rebuild for now.

Forum software patched and server upgraded.

Any problems let me know.

Cheers,

Calum

Took the bike on my first little outing to the Forest of Dead yesterday to the Cotswold Biker Nite.

Saw this GAWGEOUS Honda NS400R

Didn't know these were even a thing and it was utterly stunning in the flesh.

Was extremely quiet as it set off down the road.

@MadGyver

It's not my thing, I am not sure I would have gotten one if my Dad wasn't massively into them. But I do get it, they're fun to ride.

It's a shame you can't get any viable options though, but I'm pretty sure the bottom ends are all the same, so if you can get the 125, you'll easily be able to slap on a bigger bore to get a few more ponies.

This rides pretty well to be fair, seems to pull well for what it is.

Last week I took ownership of a new motorbike for my collections

It's a 1979 Piaggio Vespa Douglas with a Malossi 210cc kit and a full nut and bolt restoration. I mainly bought it as it's registered as a historic vehicle and as such is now MOT and Tax exempt, and the cost to insure was peanuts so it's basically ready to ride and enjoy.

It was built in 2019 and used at the local meets for a few years, so it has the odd blemish here and there, but overall it's in mint condition.

This was purchased off my Dad who, in recent years, has gone absolutely scooter bonkers.

He bought a brand new Piaggio Vespa shell in 2019 and replaced the original rotten shell.

This isn't concourse, it has lots of great mods on it, like modern front suspension and brakes, SIP digital speedo and SIP Road 2 exhaust.

I've never ridden a scooter before, but I actually really enjoy it. I enjoy the simplicity and the basicness of it. The four speed gearbox has tripped me up a few times and its quite sketchy having it on the handlebars, but is quite rewarding when you're nailing it through the gears.

I don't need any more projects on the go, although I would also like to modify this in years to come, but for now it's good to have a bike that someone has done all the work to and is basically ready to ride.

Any scooter fans out there?

You'll want to understand why that's happened before restarting the bike.

Lack of oil, incorrect piston ring end gap tolerance, or just generally tired engine, etc.

@YYHpilo Mick Abbey will rework the head for you, used to charge £30, but last time I used him he said he was going to have to up his prices.