Using a regular nut instead of a dome nut would allow some more material in that shifter.
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Winter project: upgrading time! (R6 forks and more...)
This the one you were thinking of?
Bjorn
XS650 Addict
Amazing, I love this forum. Yes, although if never been able to find it, I think this is it! I got the ones for the OEM CV carbs printed and this looks similar but for the VM. Thanks
Bjorn
XS650 Addict
Did some testing yesterday, it running great! The idle is really stable ones warmed up, which is nice. No more traffic lights anxiety haha.
Did some minor tweaking of the mix screws and throttle slide screws.
Only the cold starting is still hard. It doesn't accept any choke while starting. Leaving me to kick it without and a low rpm at idle.
Did some minor tweaking of the mix screws and throttle slide screws.
Only the cold starting is still hard. It doesn't accept any choke while starting. Leaving me to kick it without and a low rpm at idle.
My VM equipped bike REQUIRES choke for cold start and warm up, about the first minute's running is dodgy unless I am nursing (I have two separate) chokes/enricheners.
I fought poor sealing float needle valves for quite a while on several VM carbs.
There are also a couple different float settings depending on when the VM was built older carbs used a different setting.
Just a heads up if purchasing replacements, there are several VM float valve throat sizes.
Bjorn
XS650 Addict
Before I changed the cam chain (to what I believe is the right tooth), I tried the VMs. I do remember they started only with choke.
I to have two separate choke levers.
And jerry from heiden tuning recommended using the chokes for starting. He prepared these carbs. I don't know what floats I have.
I to have two separate choke levers.
And jerry from heiden tuning recommended using the chokes for starting. He prepared these carbs. I don't know what floats I have.
Bjorn
XS650 Addict
Just reading the general mikuni VM manual. Maybe its not super weird i dont need to use the choke (enricher) at the current temperature?
Bjorn
XS650 Addict
Hi, don't recall maybe it's in the topic somewhere. However my problem was have the timing one tooth off 
Running mikuni VMs now, maybe I'll try the cvk again next year.
Where are you located in the Netherlands? I'm in Zwolle
Running mikuni VMs now, maybe I'll try the cvk again next year.
Where are you located in the Netherlands? I'm in Zwolle
I'm from Burgm Frl. My next project will be a R6 fork. Will alse have to make som disk spacers. Were yours 14.5mm also?Hi, don't recall maybe it's in the topic somewhere. However my problem was have the timing one tooth off
Running mikuni VMs now, maybe I'll try the cvk again next year.
Where are you located in the Netherlands? I'm in Zwolle
Bjorn
XS650 Addict
I really don't remember haha, but read back here and you probably find it!
Sounds like it may be a tad rich on the pilot jet or mixture screw. Note that on a VM carb, mixture screw IN gives a slightly richer idle mixture, screw OUT will make it leaner. This is OPPOSITE to how it works on the stock CV carbs.
The "rule of thumb" regarding idle jet size and mixture screw is that you want to end up with the mixture screw between 1 or 2 turns out from seated.
And the basic method is to find the idle mixture that gives the highest idle rpm. So with a fully warmed up engine, tweak the mixture screws to see where you get the highest rpm. If that happens with the mixture screws more than 2 turns out, you need smaller idle jets. And with highest rpm with the screws less than 1 turn out indicates a need for larger idle jets.
And as always: Before attempting any carb tuning, the engine must be in decent condition and adjusted correctly. That means good compression, correct cam timing and timing chain tension, correct valve clearances, new or clean air filters, and correct ignition timing
Bjorn
XS650 Addict
Maybe cool too share that after fixing the timing tooth earlier this year, I pretty much rode the bike every day to work and to France for a trip this summer.
Can't wait for next season!
Can't wait for next season!
Bjorn
XS650 Addict
Time for some forum posts, did a major engine rebuild this spring. Was aiming for a winter rebuild but started too late lol.
First time diving into the engine this deep! Kinda scary but i learned a bunch.
Want to share some of my shed adventures, maybe ask some questions. These are old'ish pics. The engine is back together and running.
I had the engine inspected, mainly to inspect the crank. Feeling wise I had quite a lot of vibrations. Since I have no experience in building cranks, I figured I have somebody else do this. The crank was probably original and had about 60k km on it.
It wasn't completely shot but some interesting things were found!
First time diving into the engine this deep! Kinda scary but i learned a bunch.
Want to share some of my shed adventures, maybe ask some questions. These are old'ish pics. The engine is back together and running.
I had the engine inspected, mainly to inspect the crank. Feeling wise I had quite a lot of vibrations. Since I have no experience in building cranks, I figured I have somebody else do this. The crank was probably original and had about 60k km on it.
It wasn't completely shot but some interesting things were found!
Bjorn
XS650 Addict
First dual engine mitsubishi colt 
This was bringing it to the shop. Got it back in parts.
The crank had some misalignment. Not major, but not insignificant either. The small ends showed pitting and the whole crank was rebuilt. After some consideration I decided to go the 277° route. Main reason being I would like to reduce vibrations at higher RPM. This was THE moment to do it since everything was apart.
The gearbox was also inspected and the 5th gears showed a lot of pitting. So both were replaced. I went with the overdrive 5th.
Keeping all the worn parts. Maybe make some art out of it later.
This was bringing it to the shop. Got it back in parts.
The crank had some misalignment. Not major, but not insignificant either. The small ends showed pitting and the whole crank was rebuilt. After some consideration I decided to go the 277° route. Main reason being I would like to reduce vibrations at higher RPM. This was THE moment to do it since everything was apart.
The gearbox was also inspected and the 5th gears showed a lot of pitting. So both were replaced. I went with the overdrive 5th.
Keeping all the worn parts. Maybe make some art out of it later.
Interesting that you have a 447 motor. Is the motor an import or were 447's also sold in Europe?
I believe both 447 and 533 were sold in Europe. My 77 definitely is a 447
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