DT125R ARCHIVE

NEV · Guru

1992 4DL2 BELGARDA TZR/DTR PROJECT

CarlosRexx · Guru

RE: 38mm Keihin

eG x LoGiKzZ · Guru

they did a 38mm for the 4dl? or your putting it onto your 4dl engine? bet its going to drink petrol with that on it haha

NEV · Guru

Oh Aye it'll guzzle fuel I reckon, The 4dl had a 32mm Dellorto on it.

Plus I'll be playing around getting this added on to it too. Muahahahaha.

-- Edited by NEV on Friday 7th of September 2012 06:40:40 AM

NEV · Guru

Close Toy, lol, them there's Nitrous Oxide cartridges mate. Traffic light specials. Muauahahahahaha.

-- Edited by NEV on Friday 7th of September 2012 01:02:42 PM

ToySoldier · DTR Legend

nev wtf is that looks like co2 cartages lol

NEV · Guru

Managed to seat the carb onto the engine, modded the carb manifold by opening it right up inside, nice smooth straight through flow now, just need some straight radiator hose to couple the carb to the outlet rubber.

-- Edited by NEV on Saturday 8th of September 2012 10:11:49 PM

FunkeyMunkeyDavid · Guru

gonna be a belter that nev,proper little rocket biggrin seen those nos kits advertised,be good to see how it works out...

NEV · Guru

Need to sort out the carb with a cable for the choke,so I have the choke control on the handlebars, so I can make it run rich for the Nos, as Nos makes the engine run lean, and overheat, therefore blowing engines, blah blah blah,. this normally wouldn't be a problem with any other carb , but this Keihin has the throttle adjuster built into the choke, you pull the plunger for choke, or twist the plunger for throttle adjustment. poss look at a butterfly valve on the intake if I can MacGyver it some.

NEV · Guru

Sorted out the carb to reed block intake rubber, using an old bit of thin gauge plate cut into a 40mm strip, and a bit of car inner tube rubber cut to the same size, laid underneath to form an airtight seal, jubille clipped on, it even brings the carb off the engine about 8mm. On the hunt for a 2mm oversized Wossner piston now, if they do such a thing. Then it can all go off for a re-bore.

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bmxican · DTR Member

Wossner 2mm oversize pistons listed here http://www.forged-pistons.co.uk/webshop/wossner-motorcycle-forged-pistons/wossner-offroad-motorcycle-forged-pistons/yamaha/2-stroke/dt125r-e-x-domed-91-06-8002da-forged-piston-kit/

Not sure if your after a tzr one though.

NEV · Guru

Cheers for that link Bmxican, there's some useful info there mate.

NEV · Guru

Ford Graphite Grey metalic Carlos, a bit darker than the normal Grey that Yamaha use on their casings, the best match for that is a Rover metalic Grey, forget the actual name of it, but can find out if you need. I've got a can still in the garage.

-- Edited by NEV on Wednesday 12th of September 2012 08:16:01 AM

CarlosRexx · Guru

I love the colour scheme going on with this engine, what paint was used?

CarlosRexx · Guru

Thats proper nice. I might take a little walk to halfords and see what I can find. Whats involved in prepping the engine for painting mind? Too much effort or? Ps. Nice carb ahaha

NEV · Guru

Totally degreased for a kick off Carlos, then a good going over with wire brush wheels on a drill (large and small), cleans it up plus leaves a key for the primer to adhere to, couple of coats of primer, then about 3 coats of top coat, followed by a couple of coats of lacquer, haven't used heat resistant paint mind, as the last barrel and head sprayed with normal paint has been ok so far, touch wood.

NEV · Guru

RE: 4DL2 BELGARDA engine plus 38mm Keihin project

DT-R_bradders · Guru

Tht looks sweet nev, think the only prob ur/we gonna have is fitting it in the frame as the shock is right in the way, iv been thinking bout trying to get a custom manifold made from alloy that points the carb out to the side (left side of the bike) iv seen a pic of one made for a different bike ages ago cant remember wer i saw it tho : /

ToySoldier · DTR Legend

My mate got some alloy ones cnced for his h2 750

DT-R_bradders · Guru

Thtll be some complex programming to machine one up toyman, i was thinkin more welding one together feom a bent tube n a flat block to mount it,

Chech this beast out tho http://www.rzrd500.com/phpBB2/viewtopic.php?t=3240

NEV · Guru

DT-R_bradders wrote:
Tht looks sweet nev, think the only prob ur/we gonna have is fitting it in the frame as the shock is right in the way, iv been thinking bout trying to get a custom manifold made from alloy that points the carb out to the side (left side of the bike) iv seen a pic of one made for a different bike ages ago cant remember wer i saw it tho : /

I think I know where yer coming from Brad, maybe get hold of two Alloy/Steel manifolds and then mitre the angle at whatever it dictates, I say get two as you can go right at the end of the spigot,on the first manifold, and at the start of the other one then just tig weld together, or does it need stubbying not length?

Tell ya what though, eying up the mounting holes they look very similar to me, not given it a good looking at mind, just been sorting the engine out so its ready for a rebore, something I did come across aswell, and I'm sure it's something thats often overlooked, and can cause problems, and that was both banjo bolts that are on the head, I reckon it had been run at sometime without anti-freeze in the system, and both banjo bolts had furred up just had a pin hole for coolant getting to the head. Have took mine out anyroad as the Keihin doesn't have spigots for water pipes.

Aye Andy am going to get another DT frame and maybe gusset it for strength, and bang the 4DL into that and do a new build. I want it to go over the 100mph mark, well no harm in trying.

Am struggling to get this 89 DT started at the min, have spark and plugs getting wet now, but just doesn't want it, the electrics on it were a nightmare, chopped and changed ta fook, all sorted now mind.

I'll try and get a better side on view pic of the engine Brad, as the more I think about it I'm sure it shouldn't be a problem to fit it in. Theres a fair bit about it that sets it aside from other TZR's for a kick off the manual says that the TZR only has 4 springs on the clutch, yet this has 5,same as the DT, its got the motori minarelli casting marks all inside it, so its deffo the Belgarda.

AndyYam · Guru

100mph genuine or indicator by DT clocks? When i tried clocking my DT using my phones gps speedo it showed 62mph max which was during a run that i took it up to 9krpm. I dno what the clocks would have said as they wernt working but I would have guessed somewhere between 70 and 80. The mate I was riding with was showing 70 on his clocks when my bike was sitting at 8krpm. Am waiting to get another converter and will give it another test soon.

I'm hoping the Dt200Wr will see 100mph indicated.

With the 89 DTR, my brother 89 was notoriously hard to start when it was on the road. We used to warm the plug up over the stove as it wouldnt start after a few kicks and just flooded every time.

AndyYam · Guru

Are you gonna be running it pre mix or you gonna use the oil pump? Is your DTR running pre mix?

NEV · Guru

I have a neoprene wrist strap for the iphone, along with the Dashboard app, for the bike, that'll give me a proper speed readout, plus my hand heldGarmin 12xl gps will give a speed plus the max speed reached, I'm way way off all that mind, I'm reckoning that this'lll be finished maybe Jan,February time. Not tried the heating spark plug to get the 89 DT started yet, often worked when trying to start my lads scoots up.
Was also going to syringe about 10ml of fuel into it as well see if that gets it going, if not I'll whip the carb off it, as never bothered to clean it just banged it straight on,
As for pre-mix aye deffo, is no problem, hate relying on a pump, too expensive if it buggers up, always have the tank full of mixed, plus 5litres in a jerry can premixed, if I have to do a fairly long run, just bang 250ml in a small container, small enough to fit in a pocket or rucksack, so I can add incase I need to fill up at a garage.

DT-R_bradders · Guru

I think it could do with being longer and curved away from center, at the length its at now the float bowl sits on the engine( my fat arse mikuni does anyway lol ). also the angle of the spigots are different to the standard carb, so if the angle of the manifold was kept the same the 34mm will sit on the piss possibly upsetting the float?
So i reckon a complete re shape of the manifold to get the carb sitting flat and to be able to get a filter on it is the way forward

Do u know if altering the length of the manifold will have any affect on how it runs??

NEV · Guru

Aye I know what ya mean Bradders, about the spigot angles being different, I've noticed that the 26 & 28mm normal Mikuni's are horizontal in alignment, whereas the 32mm Mikuni on the Black & Green DT are at an angle running down from the back end, setting it on the piss slightly, seems ok with the float on that. The Keihin is the same running at a horizontal angle but the bodged up outlet connector raises it off the engine a fair bit so an play about with that to get the right angle just incase of any problems with the float. Most of the air intake/ airfilter mods will have to wait till I have it sat in the frame.
Came across this for the Wossner piston, never realised you could get a mahoosive 5mm oversize on the DT piston

If I remember right I calculated it out to 148.7 cylinder volume using a 5mm oversize piston.

-- Edited by NEV on Sunday 16th of September 2012 09:34:16 AM

NEV · Guru

I'll bet aye, and for saying they do the 150 kits for £400 on Ebay, a fair bit saved too, no matter how much a new liner would cost. plus I reckon I could get hold of some Titanium tubing from a couple of lads I know work at Royces up in Derby, would need the port mapping done mind.
Btw Dave, you know a fair bit about the Belgarda engines, whats this mean? it's stamped on the bottom end under the exhaust port. I know about the 'P' and 'SP' stamps on the barrel, SP standing for Sports Performance, presumably the 'P' stands for performance? no-one round here familiar with the Belgarda has seen this before.

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-- Edited by NEV on Sunday 16th of September 2012 11:16:54 AM

NEV · Guru

Aye know what ya mean , but the 'P's And 'SP's stamped on the barrels and heads, that I've seen on other Belgarda TDR & TZR's are the same, and same size too.

-- Edited by NEV on Sunday 16th of September 2012 11:25:34 AM

FunkeyMunkeyDavid · Guru

nearly 25cc extra would make a little bit of difference biggrin how would you get on with the liner though? mind you,i'm sure pjme make their liners to suit....

FunkeyMunkeyDavid · Guru

doesn't look factory standard if you know what i mean? normally factory marks are cast in and raised. might be a tuner/engineer mark though? loads of belgarda's ended up in the superteen race series back in the day (cheaper on parts/rebuilds than aprilias/cagivas and far more reliable)