Author Topic: Older DR 600/650 thread (Pre mid 90's) (Read 35158 times)

Wildcoast · « **Reply #300 on:** January 16, 2012, 07:44:25 am »

I'm going to tackle the carb with the BST bible, seems simple enough, best way to learn I guess....

DeepBass9 · « **Reply #301 on:** January 16, 2012, 08:17:56 am »

Quote from: WILDCOAST on January 15, 2012, 09:31:34 pm

Deepbase and Superdave, what carb set-ups are you guys running at this altitude with aftermarket pipes? Any airbox mods? My carb is next on the agenda when my jet kit arrives , wanna try eliminate as much guesswork as possible....

I have the standard carb, but I got the suz dealer to sort out the jetting. I bought the bike from Natal and the bike was running very rich with kak fuel consumption, but fixing the jetting brought it down to a more reasonable 15+km/l (right wrist dependent of course!)

Veemax · « **Reply #302 on:** January 16, 2012, 09:28:26 am »

Gents with my rebuilt BST with bone stock needle and jetting, down here in the Cape, I am getting a consistant 21 - 23 km per litre without riding like a fairy. That's very good consumption for a thumper and best I've had. My KTM640 was around 16-18 , KLR about 19-21 , and my 96 DR never got 23, but see's a regular 21....( not bad for stage 2 mod.)

I think this DR motor's cursed hot cam has a side benefit, at 5000 rpm, which is where you spend most of your time on the open road, it's sitting right bang on peak torque, where the whole dynamic plot comes together.

There is only ONE way to get a carb right, on a dyno with a properly working Lambda sensor. Get the fueling cock-on without guesswork , and for the rest of your bike's days you will enjoy best power and economy. Worth the small $ and a little effort to get this valuable data point. You have to work from the main jet backwards to form a logical chain to set up the carb good and proper.

Naturally before doing ANY of this you first validate your compression, valves, clearances, air filter, have chosen your zorst, plug gap, and all the basics ....

Also another useful observation perhaps ...the stock main of 137.5 is not lean with a Scorch pipe running a stock airbox. Definitely under full load on a cool day at the coast there is no sign of full-throttle roll-back 'perking up'. Maybe Back Then carb bikes were not set quite so radically lean I don't think.

What this implies is you can go leaner on the Reef

Geeze carbs these days .... are lean lean lean for emissions, to the point where if the bike isn't blistering hot they cough and splutter.

Even my 94DR had the mixture screw PLUGGED, and when I drilled it out I found the idle screw shut ! But I suspect my bike started life in the USA

Getting that idle set up properly was a moment of great joy for me and this bike ! : ) : ) ....no more DYING.

Lastly, most of you know I imagine, bear in mind jet kit numbers ( especially dynojet ) are not the same flow measurement as the Mikuni .... don't get lost !

volroom · « **Reply #303 on:** January 16, 2012, 09:30:52 am »

Quote from: WILDCOAST on January 16, 2012, 07:44:25 am

I'm going to tackle the carb with the BST bible, seems simple enough, best way to learn I guess....

Can I join!? I'm in Bedfordview

BTW, soon I'll be changing sprockets and chain, will change rear sprocket to 44 (from 41) to up the revs at low speed in second. Don't know if this has to do with fueling, but my DR is not happy under 3000rpm in second and you many a time do that kind of speed in town. Any comments?

volroom · « **Reply #304 on:** January 16, 2012, 09:33:35 am »

Quote from: Veemax on January 16, 2012, 09:28:26 am

Gents with my rebuilt BST with bone stock needle and jetting, down here in the Cape, I am getting a consistant 21 - 23 km per litre without riding like a fairy. That's very good consumption for a thumper and best I've had. My KTM640 was around 16-18 , KLR about 19-21 , and my 96 DR never got 23, but see's a regular 21....( not bad for stage 2 mod.)

I think this DR motor's cursed hot cam has a side benefit, at 5000 rpm, which is where you spend most of your time on the open road, it's sitting right bang on peak torque, where the whole dynamic plot comes together.

There is only ONE way to get a carb right, on a dyno with a properly working Lambda sensor. Get the fueling cock-on without guesswork , and for the rest of your bike's days you will enjoy best power and economy. Worth the small $ and a little effort to get this valuable data point. You have to work from the main jet backwards to form a logical chain to set up the carb good and proper.

Naturally before doing ANY of this you first validate your compression, valves, clearances, air filter, have chosen your zorst, plug gap, and all the basics ....

Also another useful observation perhaps ...the stock main of 137.5 is not lean with a Scorch pipe running a stock airbox. Definitely under full load on a cool day at the coast there is no sign of full-throttle roll-back 'perking up'. Maybe Back Then carb bikes were not set quite so radically lean I don't think.

What this implies is you can go leaner on the Reef

Geeze carbs these days .... are lean lean lean for emissions, to the point where if the bike isn't blistering hot they cough and splutter.

Even my 94DR had the mixture screw PLUGGED, and when I drilled it out I found the idle screw shut ! But I suspect my bike started life in the USA

Getting that idle set up properly was a moment of great joy for me and this bike ! : ) : ) ....no more DYING.

Lastly, most of you know I imagine, bear in mind jet kit numbers ( especially dynojet ) are not the same flow measurement as the Mikuni .... don't get lost !

Wow..that's why I'm not so keen tackling the carb by myself... Veemax, you coming to JHB for a weekend soon?! We need you!

Veemax · « **Reply #305 on:** January 16, 2012, 09:45:52 am »

Heh heh, I learned a lot about carbs the hard way in the last two years .... XT500 x 3 , LS650P Savage , KLR hot mods , KTM BST, DR650SE, this DR, every single cylinder bike I've touched has been a bloody challenge !

Thumpers are great and simple bikes, but they are super-sensitive to carbs.

My best advice now is start with a slide/slide-guide, and at least a fresh nozzle, on any old BST.

I have ZERO experience of Pumpers etc , guys swear by them, and I can understand why now !

Wildcoast · « **Reply #306 on:** January 16, 2012, 09:55:01 am »

Volroom I am expecting to get my USA stuff for carb today, I will start playing from then, will strip and clean carb and see whats happening , I'm in Randpark ridge

Wildcoast · « **Reply #307 on:** January 16, 2012, 10:04:55 am »

My bike was running rich and chomping fuel, prob set up for coast and the dodgy choke cable may be culprits, will wait for new pipe and do valve clearance etc. before trying to dial it in as best I can.

volroom · « **Reply #308 on:** January 16, 2012, 11:32:02 am »

Quote from: WILDCOAST on January 16, 2012, 09:55:01 am

Volroom I am expecting to get my USA stuff for carb today, I will start playing from then, will strip and clean carb and see whats happening , I'm in Randpark ridge

Saturday maybe? Would be great if we could do it together but if you want to play with it so long that's cool. My bike was also at coastal area, so thinking that it's running to rich also - hint would be that it almost doesn't need choke when starting cold..

PM me the exact address, I'm in Bedfordview. Let me know if you can do Saturday - if possible we'll start early with the BST bible next to us

Wildcoast · « **Reply #309 on:** January 16, 2012, 03:22:36 pm »

Will do volroom....

In the meantime

Wildcoast · « **Reply #310 on:** January 16, 2012, 03:23:56 pm »

Just a mock up for now, bit of fine tuning for a fit needed.....

Veemax · « **Reply #311 on:** January 16, 2012, 04:07:32 pm »

SHEEEEET !!!! That looks LEKKER like I wanna EAT IT !!!

OOOOOOOOOOOOOOOOOOOOOOO ......... thats gonna be some special one-off to confuse and amaze that is !

DeepBass9 · « **Reply #312 on:** January 16, 2012, 04:35:07 pm »

Wow, Awesome!!!!!!

Wildcoast · « **Reply #313 on:** January 16, 2012, 04:41:10 pm »

Thanks guys, geez I love that tank!!!! It's meant for a 92 , my set up on the tank rubbers differs a bit but will maak n plan!
At least the seat kinda fits and it clears the oil cooler, close to bolt on, now I'm awaiting a nice stainless pipe, should look neat!

Veemax · « **Reply #314 on:** January 16, 2012, 05:53:47 pm »

I should be mobile again with painted rims and spokes by Thursday. The front rim is much better off, as expected, hardly any internal corrosion. BUT !!!! Check those rim joins guys, I see a little split on the weld on mine, I'll go off to Link Engineering with it for a touch-up Ally Nyum Nyum weld and press the owner for coffee, I grew up throwing bricks at him, old neighbourhood fella. If you can't throw bricks at your boyhood friends, who can you throw them at ? < Years later he severed by little finger and two nerves with an axe. Now we drink scotch together >

Point is if Geoff Talbot needs a DR650 for alignment I can pop in there later this week.

I have a small job on my wifes cruiser for him to scope anyway.

That Acerbis tank really does it for me , only a snug fitting G-string bikini could look better.

volroom · « **Reply #315 on:** January 16, 2012, 08:14:27 pm »

Naais Wildcoast, love that tank. Gonna be a looker, Saulturday then. PM address pls. Cheers!

Wildcoast · « **Reply #316 on:** January 16, 2012, 08:17:12 pm »

That snug fit will require some heavy drilling, the bike the Acerbis was designed for has a pipe between the two mounting rubbers, mine has a solid steel bar, welded to the flanges.

Veemax if you could use your bike as a jig for Geoffs pipe fabrication I would be eternally muchos bottle of brandy greatfull indeed, he has my original pipe to work off.

volroom · « **Reply #317 on:** January 16, 2012, 09:18:22 pm »

Looking to fit tyres in the near future: nice 50/50 ones. Had a set of Metzeller Enduro's slip through my hand the other day at almost half price. I do not want to pay almost two grand, had to pay almost two and a half the other day for the GS tyres. So, any bargains out there?

Wildcoast · « **Reply #318 on:** January 16, 2012, 09:26:28 pm »

I'm also looking at tires in the near future, they must be fuggen tough I been checking the threads its either the kings, heidi or mitas on my shortlist.

Happy with my Heidi rear, have a trailwing up front great for tar Kark offroad though , last trip two up in the sand SWAMBO thought I was screaming with elation as we snaked along, meanwhile it was terror.

Veemax · « **Reply #319 on:** January 17, 2012, 06:40:15 am »

Paid R780 for a King 5.1" rear yesterday , same as I put on my 08DR a few weeks back, Le Cap's advice , gonna give 'em a try.

Seem hard as nails , should go some distance, but I'll be cooling off on the knee-down on Franschoek pass now !

Did this for fun this morning with my coffeeeeeeeeeeeeeee .........

Old DR rear wheel bhp 42.6 @ 6700 rpm New DR rear wheel bhp 37.4 @ 6500 rpm, ja hey , the oldtimer makes 14% more rear wheel ooomph. Also 6% more TALKS.