Search found 478 matches

by MK
Wed Mar 27, 2024 3:52 pm
Forum: Custom Projects/Restoration
Topic: Top case mod
Replies: 2
Views: 46

Re: Top case mod

DEA Engineering offers an upper case for that purpose:
https://www.facebook.com/share/p/XRwcaSXxP9wtD3CZ/
by MK
Tue Mar 19, 2024 3:12 pm
Forum: Custom Projects/Restoration
Topic: RZ500 engine in R3??
Replies: 4
Views: 186

Re: RZ500 engine in R3??

You noticed the tiny single brake disc, did you?
So you'd at least need to use a different fork/ front wheel with a dual disc setup.
by MK
Sat Jan 13, 2024 3:18 pm
Forum: Engines
Topic: Engine start problem after TSI mods
Replies: 16
Views: 681

Re: Engine start problem after TSI mods

From what's written the diagnosis is pretty clear. The owner is not able to reach the required starting rpm by kicking. Possible countermeasures: - 125 PSI is more or less a medium compression. Reducing it doesn't really make sense as some 95 PSI is the required minimum. - Open/closed PV has around ...
by MK
Tue Nov 07, 2023 1:04 pm
Forum: Ebay Alert
Topic: Very Rare 1986 RZ500S in Germany
Replies: 5
Views: 9678

Re: Very Rare 1986 RZ500S in Germany

What's he dreaming at night? 40k for a stinky old 500?

He claims tires would be original, but that's Metzeler ME33 which were not. (OEM should be Bridgestone)
by MK
Sat Jun 03, 2023 6:05 pm
Forum: Engines
Topic: YPVS Curve with Jollymoto and Modificate YVVS unit
Replies: 4
Views: 1176

Re: YPVS Curve with Jollymoto and Modificate YVVS unit

Have a look here and check out curve 18 or 16. https://www.rd350lc.de/downloads/MK-Dokumente/en/Manual_PV_Modification.pdf (Curve 18 equals RZ500 Mod_2 in your manual) Or in other words: start opening around 7500-8000, end opening a few hundred rpm before peak rpm (10500 - 12000). Unfortunately the ...
by MK
Sat May 20, 2023 12:54 pm
Forum: Engines
Topic: 1984 RZ500 clutch slipping BADLY
Replies: 14
Views: 2903

Re: 1984 RZ500 clutch slipping BADLY

I used Motul Transoil 10W-30 - bad? Suggestion on what to use if the Motul Transoil is not optimal. I'll try to man-splain it: bad - worse - Motul Transoil Long story: Use ANY other two-stroke gearbox oil, usually in spec SAE75 or 80. I used Bel Ray MC4 for ages and the one and only time I ever put...
by MK
Tue May 16, 2023 2:23 pm
Forum: Engines
Topic: 1984 RZ500 clutch slipping BADLY
Replies: 14
Views: 2903

Re: 1984 RZ500 clutch slipping BADLY

That sounds more like an assembly issue than a clutch issue. Grab your workshop manual, disassemble everything and re-assemble it reading everything twice and thrice. If it's that low torque when the clutch is engaged, then it's not the usual warped steel plates or worn springs. This has to be a ser...
by MK
Fri May 05, 2023 5:37 pm
Forum: Engines
Topic: end of restauration
Replies: 15
Views: 4206

Re: end of restauration

I used Bel Ray MC 4 for ages in all of my two-strokes. As a couple of people recommend Motul Transoil, I gave it a try with exactly your results. Neutral was hard to find and overall it felt like clutch drag. Drained the oil, filled with the usual Bel Ray - problem solved. Unfortunately MC4 was disc...
by MK
Thu Mar 23, 2023 3:52 pm
Forum: Engines
Topic: RD500 PV Closed Exh port timing
Replies: 4
Views: 1242

Re: RD500 PV Closed Exh port timing

On the 350 YPVS the valve closes around 6.5 mm at the timing edge. As the RD500 has similar diameters, you could use that as a ballpark value. As most are using Zeeltronic or other programmable boxes, the closing angle of the power valves is adjustable anyways, so you can try to play with different ...
by MK
Sun Feb 05, 2023 7:30 am
Forum: Electrical & Wiring
Topic: Poor sparks on front cylinders
Replies: 69
Views: 11035

Re: Poor sparks on front cylinders

Summer - which year? Just kidding. The piston issues despite from broken rings actually are no real "issues". #3 perfectly explained your gearbox oil consumption #4 happens more often than you would imagine (but not that some jerk plainly forgot to tighten it - they come loose, if you don'...
by MK
Fri Dec 02, 2022 11:48 am
Forum: Track Days
Topic: TRACK DAY BEAST
Replies: 6
Views: 1677

Re: TRACK DAY BEAST

I do trackdays on a regular base and I happen to have such situations all the time. From both perspectives, BTW. My strategy is easy: If someone annoys you either way and it can't be resolved by going fast enough, just calm down. Go through pitlane and he'll be half a lap away. Done that many many t...
by MK
Tue Nov 08, 2022 3:34 am
Forum: Engines
Topic: Just lost the mid-range on my modified RZV500R
Replies: 19
Views: 4668

Re: Just lost the mid-range on my modified RZV500R

BTW: On my RD350's an engine rebuild (i.e. new pistons & honed bore) typically makes it require a slightly richer setting, if the old state had a rather low'ish compression (worn bore, rings stuck due to carbon) Especially on the EFI bike this is extremely visible as I'm running AlphaN which mea...
by MK
Sun Nov 06, 2022 11:47 am
Forum: Engines
Topic: Just lost the mid-range on my modified RZV500R
Replies: 19
Views: 4668

Re: Just lost the mid-range on my modified RZV500R

the only odd thing found so far are the YPVS and ignition values in the Zeeltronic which are nothing like the ones the dyno guy put in This will have a huge effect, so that'll be my #1 suspect. But they don't change on their own. Someone has either changed that or missed to save optimized settings....
by MK
Wed Sep 21, 2022 5:13 am
Forum: Suzuki RG500 Gamma
Topic: Rg500 fork issue
Replies: 2
Views: 1209

Re: Rg500 fork issue

That sounds like too much oil in the fork legs. Usually you adjust an air chamber length above the oil level. But this has to be done at full fork travel. If someone does it with a fully extended leg, the air chamber is much too small. The effect would be as you described - a much too hard fork that...
by MK
Wed Aug 17, 2022 3:54 pm
Forum: Engines
Topic: 47x carb upgrade?
Replies: 12
Views: 3464

Re: 47x carb upgrade?

In 1985 Yamaha released some additional pages to the OEM maintenance manual from 1984. In those pages they stated the first version contained errors which were corrected by the new version. The revised version also mentions that the original version had DR9ES as spark plug and 1.95l of coolant which...