Diff'rent Strokers

[Howie]

To cut a long story short........

A few years ago I bought a Dt125lc field bike, it was erm...... not good But then I paid next to nothing for it.

Anyway, I had to ditch the frame (dangerous home welding etc) but the engine/carb etc were good, very good in fact.

So I wouldn't mind doing something with it. Maybe an early TZ race rep for the road???

But I would like to know which engine I have. I know the Rd125lc came in restricted & de-restricted form (so I assume the Dt did too?), so how do I tell? Is it just down to the engine number? Which is present But I would doubt is the original engine.......ho hum!

The engine I have has a big bore conversion but I have no idea of which make, does anyone know of a manufacturer of big bore conversions for this engine? And if so, what size would it be 175cc/185cc?

Any info you could pass on would be appreciated

[Gillinghampaul]

If the engine number starts 10 w i believe this is the derestricted model,
does it have a powervalve fitted?
And some pics would help no end!
Im by far not an expert on these engines but 2 of my bikes have them so iv picked up a few things over the time!
Also if you decide you would rather have an engine shaped space rather than the engine i think that engine with a big bore should slot nicely into my gag bike!
Any other questions just ask ill try and beas helpful as i can
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Gagging for it

[Gillinghampaul]

Also speakto fletch as he has a big bore for one of those but cant remeber the make,
Its in the gag section though. Also i think the only real differences in power came from the carb and the use of a power valve eg my engine is the standard uk and has a blanking plate instead of the powervalve.
And i also think but am not sure that the dt had a slightly different bottom end, maybe had one more mounting point at the rear? Again not 100 percent on this.
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Gagging for it

[Howie]

Thanks for the info GP, I'll have a look at the engine numbers tomorrow.

The carb itself has 10v written on it, as has bits of the engine, so fingers crossed

Mine has no power valves, not in the big bore or the spare barrel I got with the bike but from memory I'm pretty sure it has two mounting points to the rear of the engine.

I'll try to pop some pics up before the weekend.

[Gillinghampaul]

Could well be a full power motor you have there then!
I think the dt had two rear mounts and the rd and tzr only one but as i say im not a hundred percent on that,
And any idea on the bore size of the big top end?
If its a newer engine they also did a dt 200 thats about 10mm bigger bore than the 125
Oh and about 35 brake!
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Gagging for it

[cinder]

if the motor is 10w it must be an early motor so the likelyhood is it will be an autisa big bore.check the head has its combustion chamber opened out to match the bore,most wer'nt dont worry about pistons cos they can be modded to take dt/it 175 pistons
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g king

[Howie]

Right, finally got round to taking some pics (been busy coming up with rubbish ideas for 2013 ride outs )

Here is a pic of the big bore barrel
[img][/img]

The other side
[img][/img]
Notice the nasty weld, I didn't do that by the way!

And looking down inside
[img][/img]

Top advice about the combustion chamber cinder, I didn't even think about that.

So any ideas on the make then chaps?

[Gillinghampaul]

I need that on my gag bike!
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Gagging for it

[Howie]

You can't have it GP

Unless I fail to find a frame for it

[Gillinghampaul]

I know! But it would be pretty good in a gag frame!
I was thinking of using a dt200 lump in it if i can find one!
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Gagging for it

[fletch]

Looks like its the same as my Autisa 175cc big bore kit
I can take some pics and post them here for you to compare if u wish, i should get some shed time tomorrow

[Howie]

That will be much appreciated Fletch,

Cheers fella

[cinder]

i'm pretty sure its an autisa,the cylinders are good but pistons are a bit poor ,thats why people change them for dt/it depending on your port timings.
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g king

[fletch]

Here's pics of my Autisa big bore kit



Looks to me to be the same as yours Howie, what do you think?

[Howie]

I reckon you're spot on Fletch, that looks to be exactly the same as mine, many thanks to you sir.

One question though, how does the head fit on yours? Is it somewhat erm.... out?

Mine seems to be 2 or 3mm out. Its almost like the head sits a bit lopped sideways. I'll pop a pic up so you can see what I mean.

The engine ran lovely when it was in its dodgy frame & pulled like a good un, so I'm not worried, its just it doesn't look quite right.