OzVMX Forum

Marketplace => Wanted => Topic started by: ChrisACT on August 13, 2009, 10:28:21 pm

Title: Yamaha DT2 or DT3 engine and/or parts
Post by: ChrisACT on August 13, 2009, 10:28:21 pm

Hey,

I'm looking for a DT2 or DT3 complete engine or part thereof.  Or even some bits and pieces.

Let me know what you've got and I'll see if I'm interested.

Chris

Title: Re: Yamaha DT2 or DT3 engine and/or parts
Post by: Freakshow on August 14, 2009, 12:37:51 am

which parts do you want ? 450 or later 5 series / mono shock motor ?

Title: Re: Yamaha DT2 or DT3 engine and/or parts
Post by: ChrisACT on August 14, 2009, 04:11:23 pm

Quote from: Freakshow on August 14, 2009, 12:37:51 am

which parts do you want ? 450 or later 5 series / mono shock motor ?

Preferably 1972 DT2.  But DT3's were the same.  I'm not sure how compatible things were with the later DT250 motors.  The engine I have now is DT1F reed valve.  Whatever the engine I go with, it has to be road legal and bolt into a DT1F frame.  It will not be used for competition so era rules are irrelevant.

In particular I'm after a cylinder.  Would be nice if it was original bore size or at least not more than 2nd oversize.  Unmodified porting would be an advantage too.  But if anyone has bits and pieces lying around that they would like to liquidate, then some spares might be handy.

Title: Re: Yamaha DT2 or DT3 engine and/or parts
Post by: 52 on August 14, 2009, 04:50:25 pm

May have cyl Chris, Ring me 0427157452

Title: Re: Yamaha DT2 or DT3 engine and/or parts
Post by: 52 on August 14, 2009, 05:04:07 pm

Just measured it Chris-71mm-assume thats a mm over-still bore looks OK

Title: Re: Yamaha DT2 or DT3 engine and/or parts
Post by: ChrisACT on August 14, 2009, 05:51:08 pm

Have the ports had any work or are they stock?  How much you want for it?

Chris

Title: Re: Yamaha DT2 or DT3 engine and/or parts
Post by: facthunt on August 17, 2009, 12:14:08 am

I've got a DT2/3 cylinder, measures 70.5 nominal, looks good.

Title: Re: Yamaha DT2 or DT3 engine and/or parts
Post by: ChrisACT on August 21, 2009, 10:52:12 pm

I'm also looking for a DT2 ignition coil (or compatible) and a carb boot with an ID of 45mm (to fit a 36mm Keihin PWK carb) that will fit the DT2 reed block (maybe RT2 carb boot?).

Anyone?

Title: Re: Yamaha DT2 or DT3 engine and/or parts
Post by: Nathan S on August 22, 2009, 12:05:32 am

Ignition coils are generic points Yamaha. I can help - discounts by the dozen.

The standard set up for the carb is an aluminium block with a 'flange mount' carby. Dunno if anything else is the same (and I can't check after I off-loaded all my reed valve stuff), but you're welcome to go through my small pile of intake boots to find anything that's the same.

Title: Re: Yamaha DT2 or DT3 engine and/or parts
Post by: ChrisACT on August 22, 2009, 12:18:40 am

Thanks Nathan.

The RT2MX had a rubber boot (I imagine they're rare as RHS though).  Besides, I doubt it'd fit the 36mm PWK anyway as they had a 34mm Mikuni (VM34SC).

The DT2 reed block was common to a lot of bikes:

DT2/2MX/3 all years
IT125G/H '80, '81
IT175 D/E/F '77 - '79
MX125C '76
RT2/2MX/3 all years
TZ750A '74
TZ750D '77
YT175J -82
YZ100D/E/G/H/J/K '77 - '83
YZ125C/D '74 - '77
YZ125E '78 - '80
YZ125X '76
YZ175C '76
YZ80G/H/J/K/L '80 - '85

But I don't think any of these used 36mm carbs.  I guess the other option is that I make up an adapter plate for the carb boot.

Title: Re: Yamaha DT2 or DT3 engine and/or parts
Post by: vandy010 on August 22, 2009, 08:19:27 am

check the monoshock DT400. i know the bolt pattern on the reed block is the same as the DT2 etc, so maybe the rubber intake boot  could be what your after.
failing that, if you can "jam" a 32mm carb into the smaller DT125 rubber intake boots, then maybe you could "jam" a 36mm Kiehin into one of these ones you speak of.

Title: Re: Yamaha DT2 or DT3 engine and/or parts
Post by: ChrisACT on August 22, 2009, 09:14:44 am

Thanks for the tip, vandy010.  I'll definitely check that one out.

Nathan, you reckon you might have a DT400 intake boot lying around?

Title: Re: Yamaha DT2 or DT3 engine and/or parts
Post by: LWC82PE on August 22, 2009, 12:21:46 pm

hows this?
http://cgi.ebay.com/ebaymotors/77-YAMAHA-DT400-DT-400-ENDURO-INTAKE-MANIFOLD-8_W0QQcmdZViewItemQQ_trksidZp3286Q2em20Q2el1116QQhashZitem3c9eca48a4QQitemZ260362094756QQptZMotorcyclesQ5fPartsQ5fAccessories

Title: Re: Yamaha DT2 or DT3 engine and/or parts
Post by: ChrisACT on August 22, 2009, 01:18:21 pm

Quote from: LWC82PE on August 22, 2009, 12:21:46 pm

hows this?
http://cgi.ebay.com/ebaymotors/77-YAMAHA-DT400-DT-400-ENDURO-INTAKE-MANIFOLD-8_W0QQcmdZViewItemQQ_trksidZp3286Q2em20Q2el1116QQhashZitem3c9eca48a4QQitemZ260362094756QQptZMotorcyclesQ5fPartsQ5fAccessories

Thanks for that.  I've asked the seller to measure it for me.

Title: Re: Yamaha DT2 or DT3 engine and/or parts
Post by: vandy010 on August 22, 2009, 05:59:53 pm

yep, i reckon thats the same bolt pattern but i'm pretty sure it's still to suit the 32/34mm mikuni.
same as YZ125x,d,e,f. i think it's only the angle of the carby mount that differs.

Title: Re: Yamaha DT2 or DT3 engine and/or parts
Post by: ChrisACT on August 23, 2009, 07:59:39 am

The DT400 manifold seller replied and the measurements are 70mm x 52mm bolt spacing (which fits my reed block) but the carby spigot is only 39mm.  I need 45mm for my carb.

So that one's a dead end.

Title: Re: Yamaha DT2 or DT3 engine and/or parts
Post by: jimson on August 23, 2009, 07:08:57 pm

Chris how big a difference would it be if you but the carbie against the intake and put a sleeve over the connection  :-\ jimson

Title: Re: Yamaha DT2 or DT3 engine and/or parts
Post by: ChrisACT on August 23, 2009, 09:39:39 pm

To be honest, I'd never considered it.  I'd have thought that would give no advantage over running a 34mm carby.  Would it not be better to run a 34mm carb rather than running a 36mm carb through a 34mm manifold.

Title: Re: Yamaha DT2 or DT3 engine and/or parts
Post by: tony27 on August 24, 2009, 09:15:16 am

Its a very common mod on modern trials bikes when fitting larger keihin flatslides

Title: Re: Yamaha DT2 or DT3 engine and/or parts
Post by: ChrisACT on August 24, 2009, 09:59:57 am

Has anyone ever dyno'd it to see how it compares with running the right sized carb for the manifold?  My engine sim seems to think it would not be such a great idea.  Running the 36mm carb through a 34mm manifold results in at least a 1HP loss over most of the curve compared with running a 34mm carb.  At no point in the RPM range is it better.  So, it'd be easier and better to run the 34mm.

Bear in mind that's not real world data, just a MOTA simulation so it could be wrong.