DT125R ARCHIVE

Calum122 · Guru

RE: 4DL TZR Engine Unmaintained!

scrimsmustang · DTR Mechanic

Yes Callum built and fettled by them in Italy for Belgarda I agree but in reality its no different really just the topend and the gearing. But it is tuned from the factory and that does make it special and rare.

Luke · Guru

But it isn't £300. It's £500 once you've rebuilt it.

Can get a whole DTR engine and get it fully rebuilt for about £300-£350. So a fresh fully rebuilt engine, versus one that has a couple of stamps and a logo on it. Nah, would rather the new DTR engine.

Calum122 · Guru

Lol. But you aren't building your bike are you. I'm only using the best of the best on my bike. It's a one off. So yeah it is worth it. To have a unique engine put into a unique bike. I'd pay the premium for it.

MDK · DTR Legend

would say unless you have owned a tzr 4dl you should hold your comments the engine totaly blow standard the dtr engine out of the water in terms of feel and speed . you can say I am talking crap but my tzr 4dl used to scare me a little even close to 80 mph it seemed like it still wanted to keep going no bogging put or holding at a screaming speed it still had more to give yes we can say that was partly the bike also .

Calum122 · Guru

Something positive. Thank you mdk mate. Getting negative vibes here lol. It's a lot of money to spend. I appreciate that. And yes the guy might have fleased me a little. But i was under no impression that the engine could go straight in. I looked at the price. I looked at other ones on the market. And i said to myself. This engine wants a full rebuild and the cost of the engine iteself. Which is why i knocked it down a few. I'm happy with the price i paid. I'm actually chuffed to own it. I'm going to put some serious time, money and effort into it. And i will get it dyno'd to show the results. My aim is to achieve rs125 power out of a dt. Thats about 26bhp. Maybe a little less. Thats a 10 bhp increase over stock dt's.

Either way it's going to be interesting. And i'd prefer it if it was left with constructive criticism.

To be fair the engine rotates freely. I bet theres nothing wrong with the bearings. But once its cracked open i don't want to do anything else other than top end rebuilds.

slob · Guru

As we all know money isn't everything. Sometimes when stuff comes up you just have to pay as long as it makes someone happy. What's £300 two nights out with nothing to show for it or a nice little project that you can sell on if you wanted.

MDK · DTR Legend

say your aim is 26bhp was the 4dl not already 33bhp unrestricted

http://en.wikipedia.org/wiki/Yamaha_TZR125

Calum122 · Guru

MDK wrote:
say your aim is 26bhp was the 4dl not already 33bhp unrestricted
http://en.wikipedia.org/wiki/Yamaha_TZR125

At the crank maybe. But not at the wheel. Remember. Power is lost through the transmission AND the final drive.

Also this is not a tzr. Its a dtr. I'll be using a dep pipe and not the belgarda sp1 pipe. So won't be getting full power.

Low expectations and tben anything better than that is a bonus

MDK · DTR Legend

she gona be a beast the 4dl engines are awsome .

cant wait to see this done and in the bike so you can video the top speed I expect nothing less that 80mph min with you screaming like a girl in the video back ground lol ..

Calum122 · Guru

MDK wrote:

she gona be a beast the 4dl engines are awsome .

cant wait to see this done and in the bike so you can video the top speed I expect nothing less that 80mph min with you screaming like a girl in the video back ground lol ..

DT will do that anyway.

Calum122 · Guru

Just bought 32mm vhsa dellorto carb for it. The carb that came with the tzr r :D.

Don't know its condition. Said to need a clean but about it. What should i be expecting from a 20 year old carb? Lol. Probably a complete overhaul knowing my luck.

MDK · DTR Legend

could be clean or could be full of varnish type residue I stripped everything burnable off some and put them over flame on cooker it soon turns to liquid and bubbles out but if its a well used carb it still maybe clean inside .

Calum122 · Guru

So very small update.

Paid and bought for a VHSA Flat slide carburrettor 32mm. It's actually in very good shape for its year. Surface damage to the carb. Internals are semi good. The floats have a bit of corrosion on them. Nothing major. Will get round to replacing that. The slide chamber is good. Few signs of wear but nothing extreme. Definitely useable on the whole!

Above I didn't clean it.

Use some 'Professional Carb Cleaner'.

Actually did a nice job at removing grime. Then I found this in the cupboard lmao! I think I need a bigger one but I broke the carb down and cleaned it all up.

Looking good now.

Also managed to get a 4DL inlet manifold which obviously can take the bigger carb. So pleased about that. Cost about £100 in total for the carb and the inlet and cage. Will strip the cage down and fit carbon reeds into it.

DT is running out of its nine lives. This month I HAVE to get that 3MB00P barrel rebored and fitted to the standard engine. I start a new job next month and can't have the DT top end going. So I'm going to rinse the bars and get the standard engine back to perfect health.

So the tuned barrel will be on until I get the 4FU tuned and the 4DL repaired. As of now this thread will be dead until some real progress is made.

-- Edited by Calum122 on Thursday 8th of August 2013 09:59:30 AM

MDK · DTR Legend

lazey fecker cleaning it in some old deep fat fryer thingy lol ... get some wire wool on it polish up all shiney and clean

-- Edited by MDK on Thursday 8th of August 2013 03:22:19 PM

1DOWN5UP · DTR Respected Member

Thats a round slide carb mate looks good tho

Calum122 · Guru

No. It's a flat slide carb. Thanks though.

1DOWN5UP · DTR Respected Member

Oh i get ya looks strange. much easier to remove than fiddling with the screws on dt carbs

Calum122 · Guru

Lol. Ultrasonic cleaner. Good tool to have. Will buy a bigger one.

Calum122 · Guru

So guys small update.

Start my new job Monday so excuse me I've been preoccupied with that at the mo.

Managed to get my hands on a GoPro HD Hero 3 which I'm pleased about :D It is just the base model unfortunately :( But the picture quality is superb nevertheless!

So Where am I at the moment?

Well I'm waiting for my new pay to get that 4DL rebuilt but for the moment I need my bike to use everyday. So I've stripped the old 3MB down.

I had prematurely bought 0.5mm Wossner piston to go in it. Took it all apart and I was pleased/gutted to see that the bore is in immacculate condition and thus rebore not necessary.

Not to worry. I've decided to use the 4DL's top end on my bike for the moment.

So went to Yamaha for a rebore. Looks like they've done a lovely job. Most pleased with it.

I'm still running it in at the moment. It works is about all I can say for now. Haven't taken it past 6K revs but it's all working lovely (touch wood).

Plans are to get that 4DL stripped and rebuilt. Then get my old 3MB cylinder sent to Yamaha. Tolerances checked and new wossner Piston kit for it.

Put that 3MB Back on to the standard DTR bottom end. Send the 3MB00P off to a two stroke specialist for the exhaust ports widening and gas flowed boost ports. Thinking of getting the cylinder head machined down to get closer to the original spec compression ratio.

Eventually get the 4DL setup up and running and into the DTR. Will update this thread with how the rebuild is going as and when it occurs.

As soon as that cylinder is ran in I'll use my GoPro to give it some welly down a dual carrige way or summit for you guys to see.

yamahayz125 · DTR Senior Member

MDK wrote:

she gona be a beast the 4dl engines are awsome .

cant wait to see this done and in the bike so you can video the top speed I expect nothing less that 80mph min with you screaming like a girl in the video back ground lol ..

their not that good of a engine ad rather spend the money on getting a standard dt engine ported and set up with a bigger carb than waste money on a engine thats got a few silly stamps on it

Calum122 · Guru

Yeah fck it. Put it in the bin i reckon.

MDK · DTR Legend

yamahayz125 wrote:
MDK wrote:

she gona be a beast the 4dl engines are awsome .

cant wait to see this done and in the bike so you can video the top speed I expect nothing less that 80mph min with you screaming like a girl in the video back ground lol ..

their not that good of a engine ad rather spend the money on getting a standard dt engine ported and set up with a bigger carb than waste money on a engine thats got a few silly stamps on it

well from the little I know ..my tzr 4dl was awsome and never missed a beat in the year I owned it riden and raped every day of the week and murderd most 125cc bikes that came along side me .

1DOWN5UP · DTR Respected Member

I think its good cal how many dt's you gunna see with that engine in them . even if the performance gains are not massive its got to be a bit different since its from a tzr. We will all just have to wait an see your verdict on it how much did yam charge you for a rebore

Calum122 · Guru

29.35+ VAT bargain i thought.

Yeah cheers mate. The idea is actually borrowed from nev. so it's not origina" i'm afraid :(

AndyYam · Guru

Hey Cal hows things going. Not been on here much recently. Loads going on. Ignore the tards with their own ideas on whats best. You're the one doing it and regardless of the costs etc etc, if it makes you happy then thats where the importance lies. Sounds like you've got a nice little collection of barrels and engines there now!

If you keep them all for some time then you'll certainly be doing well when the 4dl's start rising in price. Look at the 250's at the moment. 3, 4 5 grand. The MM 4DL engine will be worth good money eventually.

Hows it running in then? Hopefullt you've done a few heat and cool cycles now and can give it a test?

Make sure you keep checking plug colours and set the carb up right with regards to jetting and settings. And also make sure you keep the air filter clean. I think i remember seeing that you got a yz125 now? Howa that going? Where abouts are you too and where do you ride the YZ?

Calum122 · Guru

Yeah mate. It's good to see you back. Have missed your input the past few months.

Yeah i have now. This 3mb0p. Hhmm. Don't know what to say. It's funny you mention plug colour i've literally just cone back from the garage from having a check. Done about 150 miles. Plug colour! It's like a fecking rainbow!

I've got soot black from using loads of oil on the build. A lovely brown colour. Look close enough and it may it may not look like white specks from blistering! Hope not.

So today i went to 8 k revs. Once. After warming it. Seems to pull lovely. However i did this the other day and it was shocking. If you go half throttle. Wait for the power to build the. Go full chat it seems really good.

At the moment i'm only riding under 6 k revs. And at 1/4 throttle. So thats probably why.

That 4dl needs a rebuild i've decided. I'm pleased wth your positive feedback. As i respect everyones opinion but you're quite knowledgable so thats nice. That said so is scrin :(.

The yz. Yeah that's a point. I've got a shocking load of videos from my gopro. I'll sort out the upload and post it up.

Went to ashdown mx track on sunday. Insane trck.

AndyYam · Guru

Get some close up photos of the plug.

I went to Golding Barns on Wednesday and usually go to Mill lane Track.

Finally got my go pro set up right on wednesday. Very shaky and you can hear the helmet hitting my neck brace all the time. Wanna try out joyce green or the milk run soon. Where abouts you live? you travel far to tracks?

Calum122 · Guru

I live in cheltenham. So it was what 40 odd miles to Ashdown. Probably wouldn't go any further than that. Bit of a mission. Probably won't be out on it for the rest of the year now :( Will go away. Maybe make a project out of it :D

Here's a video of my brother on the YZ round Ashdown. That track was far too technical for me :(

I'm dreadful off road

AndyYam · Guru

That place looks amazing! i wanna go there!