Show Posts

This section allows you to view all posts made by this member. Note that you can only see posts made in areas you currently have access to.

Messages - John Orchard

Pages: [1] 2 3 ... 183
Tech Talk / Re: Your thoughts on a carburation matter?
« on: March 23, 2019, 08:04:57 AM »
Is the pilot jet installed and clear?

Yep all basic stuff is right. l have swapped up & down in pilot sizes, and air-screw settings.

Tech Talk / Re: Your thoughts on a carburation matter?
« on: March 22, 2019, 12:31:48 PM »
I feel that a piston port engines slide would be higher compared to a similar reed engine due to the pulsing nature of the intake at idle. Quite a lot of the charge is pushed back out of the carb as the piston starts back down the bore which means a higher slide position is required to get enough air/ fuel for idle.

If there was a problem with the idle circuit of the carb being to rich or lean the high slide to get it on the needle would mean very high idle and poor starting.

You could stick in a bigger pilot jet as a test if it really bothers you or play in and out with the air bleed screw to see what effect that has.

Yeh l was thinking PP the reason, l'm going to try a piston with a 4mm longer skirt to see if that changes things.

Tech Talk / Re: Your thoughts on a carburation matter?
« on: March 21, 2019, 08:53:30 PM »
Sorry for the confusion, the slide idle positioner is screwed all the way in, looking in the venturi yes the slide is high.

The idle mixture screw is set at 1 turn out.

The bike idles nice at the high slide setting, if l back the slide down the engine stops.

Tech Talk / Your thoughts on a carburation matter?
« on: March 20, 2019, 09:58:14 PM »
On a piston-port 250, bikes starts & idles fine but the idle adjustment screw is all the way in, having quite a high slide setting.

Any ideas why it needs a high slide setting at a low rpm idle?  Too rich needing more air?

Vintage Track / Re: XT500, de rake? Better turning?
« on: March 14, 2019, 06:40:28 PM »
That would help with sharpening up the turning wouldnt it?

Yes the 79,80,81 TT500 triples have less off set than the early TT500 models

lt will put more rider effort into the steering process, gives the bike more trail, hence more stability at speed. Every bike l own l have reduced triple-clamp offset to get more trail.

General Discussion / Re: Track time
« on: March 13, 2019, 12:52:43 PM »
CD is great! but unfortunately it doesnt change venues like it used to. I cant justify driving from Melbourne to Queensland for it.. :'(

I have really enjoyed CD the few times I’ve attended.

This year there are 2.
1. Classic Dirt at QMP (new venue) May 3-5th
2. Classic Weekend (Ride) at beautiful Green Park Connondale (Venue for CD the last few years) June 7-9

Yep l feel the same but l guess there Qlders that don't want to drive to the Bonanza :-)

Yamaha / Re: Motocross seat conversion for Yam DT1?
« on: March 04, 2019, 09:32:05 AM »
All sorted now, Ron Whitmore helped me out with an old RM125A,B,C seat that only needed a slight reshape of the front mount bracket.

Pit-Replica in Tailand are making me a cover with the 'RM125' removed from the side and putting YAMAHA across the back.

Yamaha / Re: Yam clutch spring specs- 90501-20122 & 90501-20124 ?
« on: March 04, 2019, 09:27:12 AM »
Thanks Guy's, l was interested in the two numbers that are quoted for the DT/RT's as l would have thought one set might be a little stronger, they share much the same other clutch components.  l am hesitant to go an aftermarket set of heavy-duty springs incase they make the lever pull too stiff, coil-bind or put undue stress on the worm-drive push mechanism.

Yamaha / Yam clutch spring specs- 90501-20122 & 90501-20124 ?
« on: March 02, 2019, 12:59:18 PM »
Anyone with a range of Yamaha Clutch springs in stock be able to tell me the difference the following two clutch spring parts?


They both are listed for  a great many model Yams, both are listed for DT1 but one is listed for RT1; if one is a little stronger I'd like to get that one, TIA (Thanks In Advance).

Tech Talk / Re: Trying to find port timing diagram for a DT1MX.
« on: March 01, 2019, 09:48:44 AM »
That would be very interesting to a few l think, if you get the chance? Thanks. Do you want to sell it? :-)

Tech Talk / Trying to find port timing diagram for a DT1MX.
« on: February 27, 2019, 07:05:15 PM »
I'm still having no luck finding a port timing diagram for a Yam DT1MX, could anyone give me any leads please  :-)  TIA

Tech Talk / Re: DT1 clutch push revisited / update.
« on: February 20, 2019, 04:36:15 PM »
I went to order the GSX item (23200-31300) from Mick Hone,the Parts Guy suggested a GSXR600 item that all the GSX guys change to, cost me $53,it included the inner & outer parts,and has a steel worm-drive.

Took me an arvo to fit it, works great !  I had to grind-out the old alloy worm-drive in the casing, mounted it inside the case, just had to concoct some idea to hold the outer cap in place.

Thanks Gentlemen, got it running ...... farking PVL ignition!  Just had to put me workboots on and kick like fark!

My first experience with PVL, I'll be looking for a YZ ignition I think, anyone want a cheap PVL?  :-)

Tech Talk / Re: Help/ideas needed to get my stupid brain working.
« on: February 17, 2019, 11:27:42 AM »
I once was working on an Suz RGV250 that had a bad misfire, the sparkplugs were fouling, I'd heard that lifting the plug caps about 10mm off the plugs can cause an increase in voltage to the plug, allowing a fouled plug to fire. Having to jump the large gap allowed the system to build-up a higher voltage to make the jump? Sure thing, the RGV would run fine with the caps lifted off the sparkplugs!

Is there another way to increase the voltage to the sparkplug in this instance ?

Pages: [1] 2 3 ... 183