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Always loved that color.

Ill be there.  Taking 7 bikes out.  Ill have the 75 RD350, 82 YZ250, 74 RD350, YZ250x and a few scooters

XSR900 inline 3.  Should sound sweet with that 3, looks dope and #425 for a 900 should be flickable in the turns and smooth on the highway. A bit above your budget you listed tho.

I reset the timing and buttoned everything up with a 10.9 M7 bolt and 4mm washer the other day.  The timing was still spot on at 1.8 btdc.  Torqued it to 20 ft-lb per Johns recommendations and took it for a rip.  All is good and ready for Vintage Motorcycle Days later this month. 

How far are you from mount pleasant? Eric Thomas (the Kaw Shop) bored my cylinders and did some other work for me. He drag races an H1. He may not be able to do the work you're looking to have done, but I bet he knows who in PA could.

+2 on Eric, he bored my 75 350 and will do my TZ replica here soon as well.  Great guy and does top notch work.

We have an upgraded hardware kit for the Vape that works better than the hardware Vape sends in the kit. We include the M7 bolt and thick washer (4-5mm). I torque them to 20 ft/lbs and don't have trouble with them slipping or snapping off bolts.

https://www.economycycle.com/shop/yamaha-rd250350400r5ds6ds7-parts/electrical-ignitions-lighting/ignition/mzb-cdi-electronic-igntion-for-yamaha-rd250350400r5ds6ds7-street-version-hardware-upgrade/

Thank John.  Yeah that washer and bolt they send with it is not good.  The washer was cupping when tightened.

If you have both halves, well, thats how long it was:)

Any hardware store will have a tester for the pitch and dia, you probably will have to clean up your end so it will start tho.  If you find a long one, buy a nut for it too and you can put on the nut,  hacksaw it to length, then run the nut off, repeat and dress with file as necessary.  Can do with a cutoff wheel but since its hardened, maybe better to do it by hand.

Thats not a big bolt but no way that should break at 12-14, even if made of chinesium.  That said, I'd still listen to M's advice. 

The last trailer hitch I put on came with 10.9 M12 fine 1.0? 1.25? and I think car calipers are 10.9 often but will probably be too long and too big. The neighbor and I have a big ass drawer full of old fasteners I could look through if you get the spec and get stuck.  You could also tap your own if you find a long one with partial threads.

It is no problem to find the right bolt for the job.  I appreciate your suggestions.  Like i mentioned, asking will usually save time and help anyone else in the future if they encounter the same issue.  Ill sort out the measurements and post them here for that very reason. 

8.8 = roughly a grade 5. you want a class 10.9  IF you can find one.

Let the search begin.  Any idea what size and thread pitch and length that bolt is?  I know its shorter than the stock one.  Save me some time since the one i have is now a two piece.

That was my flashback Mark! lol.  My 74 did the same thing with the crane cams hybrid iggy that you helped me build when the old site was up.  Had to replace the whole bottom end on that one.

ah shit, sorry about that. must have been one of the earlier ones w out the big pie cuts. sorry about that. 

no worries lol!  that bike has a HPI ignition and runs amazing now.  The old crane cams deal worked great for what it was actually.  Ran for years like with no issues. 

So, i had a chance to pull the cover off today and check things out.  Turns out, the bolt was backing out for the rotor and i suspect the rotor slipped timing a hair when i was revving it out.  When i tightened the bolt it snapped off in the crank end.  Fortunately and unfortunately i never put locktite on the bolt and was able to drill it, then back it out with an impact driver.  I was sweating that for a bit but it backed out easily.  I found a 1/4 thick flange washer but need a new bolt.  It was an 8.8 hardened bolt in there that snapped!  Does anyone remember the torque setting for that bolt???  I plan to pick up a 10 hardness if i can locate one.

yup. could have been worse...

this was in 09 or so. same thing.

That was my flashback Mark! lol.  My 74 did the same thing with the crane cams hybrid iggy that you helped me build when the old site was up.  Had to replace the whole bottom end on that one.

The older style drum had 2 issues. One was the square trigger and the other was the rivets would loosen up over time. So several years ago, Vape changed the drum to a one piece with no rivets and a ramped trigger (trailing edge) to prevent reverse starting. With those old drums no half kicks or lazy kicks to help prevent backwards starting.

This is the new rotor, you can see the ramped trigger at the 4-5 o'clock position and no rivets on the front.


https://www.economycycle.com/shop/yamaha-rd250350400r5ds6ds7-parts/electrical-ignitions-lighting/ignition/mzb-rotor-updated-design/

John, I see you have those rotors on the site.  Guess I better put in a new order.  BTW, I picked up the adjustable preload fork caps from you and they are money!  So nice to have the sag dialed in with the simplicity of a screwdriver instead of cutting spacers over and over again.

Yesterday I went for a little spirited ride.  I recently installed some PWK's on my 75 RD.  Its pretty much dialed in on the jetting (thanks Mark for the starting point).  I took it up the road after a warm up and opened it up a bit.  I rev'd it out in 4th and when I shifted into 5th and backed off the throttle I noticed on my EGT gauge there were no numbers displaying and the bike was bogging.  I pulled into a lot and discovered the right cylinder was not running.  I shut the bike off and turned the back on and got my gauge back but it was still not firing on the right side.  After a few revs it came to life.  When I left the lot to go back home it sputtered on the right side for about 20 seconds then appeared to be fine.  I got back home and shut the bike off and restarted it again to see if i could replicate the issue.  When I kicked it over it started backwards.  I have never had this issue in the 6 years ive had this iggy on the bike. I did read on economy cycle that there is a revised rotor because of this issue.  Has anyone else experienced this before?  I feel like I have two issues going on, rich on the main causing the right side to foul and older style rotor on the MZB causing the reverse starting issue.  Let me just add, when starting the bike it will fire with just half a kick.  The idle was set very low and I only kicked it easy when it started in reverse.  Let me know what you guys think.

I've used pwks a few times on rd builds.  I can  say the y boot won't work, but long unis are fine. as far as jetting,  I've always had luck with jjj or jjh needles, about a 40-42 pilot, and 155-165 main. can't comment on 'nd' jetting. the stock cables, for low top carbs, will work but upu have to use larger ID adjusters on the pwks, stock Yamaha/mikuni ones will  thread in.

Thank you good sir 👍

I have a set of 28mm PWK's laying around I was going to use on another build but may go another direction with.  Ive been running VM28s with the DF mod for probably 18 years that dave talked me through (God rest his soul).  I have PWK air strikers on both my YZ250's using JD jetting kits and they just work great.   Does anyone know if the PWK's will work with the stock air boot and K&N filter? I really want to see how the RD responds to PWK's with the JD kit but want to make sure I have the part list sorted before I dig in.  Also, do the stock cables work with PWK's?

I got spark!  I removed the plug on the CDI box and plugged it back in.  Must not have been seated properly.  Now I have to finish getting the tank back on and fuel lines connected.  I plan to start at 2mm BTDC.  Bike is completely stock.  I ran it at 1.8 with the old setup so I may play with the timing a bit when its running well.  I have one last question for anyone running this ignition with the stock wiring loom.  Did you wire your ground into the stock kill switch to work with the key?  If so, how?  I have an idea of how I would like to approach it but I want to see what has worked for others.

try disconnecting the ac lead to the VR (regulator). Just leave it hanging.  if when that circuit is open and you get spark, that could very well be it.  you don't need the VR to get spark, BUT, if there's a short in the windings from the lighting coil to the ign coil, this might explain it.  what is the kill wire to the cdi box connected to? anything? if so, disconnect it. .02

I will try this.  Kill wire is just hanging without a connection to anything.  Ill try to capture some pics of what is wired where tomorrow and what I am disconnecting to assure I am understanding you correctly Mark. 

I had a flukey thing happen when I installed a HPI. I had the coil mounted right next to the CDI box and it wouldn't spark due to the coil causing an interference. Are yours close to each other?

My coil is in the stock location and the CDI box and regulator are under the battery in the stock location.