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Did a quick search and nothing came up so here goes.  What do you guys use to press the wrist pin out of connecting rod?  I am going to put my new top end on my RD350 in a few weeks and wanted to know if you made items or just bought a puller online.  Worried about damaging the connecting rod bearings if I get too aggressive, trying to alleviate any issues. Thanks

Looking for a quality set of tubes for my 75 RD that I plan on putting BT46 tires on.  I have read that Chuck Q recommended IRC tubes, but can't seem to find a front tube size anywhere.  Chuck recommended 3.50-4.00-18 for the rear, what sizes are you guys using and what brands do you suggest?  Also would anybody have advice on using rim tape verses rim strips, looking for pros and cons. Thanks, Brian

All, I do not take this lightly but wanted to inform the forum members if you are contemplating getting any pipes from Brazil (Dogster), they make quality products but their customer focus is lacking, especially if you have an issue after receipt of product. I will not publish any of my issues but from a business perspective, acknowledging a valid customer complaint regarding shipping damage due to poor packaging and fitment issues, resolving to the satisfaction of the consumer is not their strongpoint. As the 2 stroke world is small in regards to vendors for these bikes, I would look elsewhere for manufacturers within the states.  Don't learn the hard was as I have.  Thanks

I was looking at my motorcycle tires (IRC's) that were part of the motorcycle deal as these were "new" when I bought my RD in March of 23.  Closer inspection of the front and rear tire dates codes indicate 0617 and 5116, so these are basically 6 years old.  I know they were a real bitch to install with my spoons, may explain why the sidewalls were as stiff as hell.  Regardless, I have been looking at 90/90/18 BT46 and 110/19/18 BT46 tires for my 75 RD.  Looks like I can get a pair shipped for under $250.00 which seems like a decent price.  Few quick questions,  How old of a date code is acceptable for a new tire?  I read that 6 years max is recommended for replacement, but was wondering how long a supplier can sit on tires and what the consensus is with regards to the 2 stroke forum as to what is acceptable (i.e. how old of a tire would you mount if bought new and if you would return?  I only ride less than 300 miles a year so the newer the better in my opinion. 

I am working with our machinist at work (who coincidentally has some RD's) to fab up our own kickstand relocation kits to use with chambers.  He can model these and then cut out on CNC plasma cutter. Was wondering if anyone had some dimensions or could provide detailed pics to save some work, seem pretty simple to make and could potentially offer up to members.  Thanks

Just received my Dogster chambers, quality looks good but left side hits the kickstand spring boss, which prevents the head and rear attachment points from fully engaging.  I am reluctant to cut this off as I want to keep the bike as original as I can if I sell it someday and someone returns to stock.  The way I look at it is I could do a kickstand relocation kit and cut this boss off(not preferred), or dimple the brand new set, but have reluctance with this as I just spent ~675$ for this.  Does anyone have any previous experience with dimpling SS headers, assuming I could use my acetylene torch and get hot, use a round bar and strike with a deadblow.  Just fishing for some suggestions before pulling the trigger.

It's been a few years since I completely redid my 73 350 and cannot remember.  If you remove the gas tank, can you pull the cylinders off the stock studs or is their not enough clearance and the engine needs removed from frame? 

I reached out to Bill Bune (Minnesota) from a recommendation on this forum and his prices seem very reasonable, Has anyone had extensive porting and or boring work done, and if so what were your thoughts?  Also any advice on using Banshee pistons in an RD with the skirt modifications needed?  Thanks, Brian

Has anyone used these and if so, what are your thoughts on fit/finish/quality/performance?  Google search of their website indicated that these are ~ $450 plus shipping.  Shipping from Anaheim to Pittsburgh is 70 bucks, which is reasonable.

Had a question about the factory voltage regulator for a 75 350B. Does the adjustable metal contact (portion that is bent using pliers) actually touch the thin sheet metal spring steel to make contact when bike is not running and turned off or is there a gap between this and the thin sheet metal?  I adjusted as mine was overcharging *(by bending this tab downward) and now it wont charge- -may have went too far, thinking it may need to contact or a specific gap needs maintained.  Would anyone have a picture of this, looked in factory service manual and it states to move this but no close up pic.
  Thanks, Brian

Wanted to ask some of the forum members who(m) they would recommend for machining services.  I have some feedback already, wanted to get a larger consensus of anyone reputable in the continental US, quick search yielded few results.

Thanks, Brian

I had some time today to install my Dyna S ignition.  I determined timing with a dial indicator and roughly set timing, then once running fine tuned with a light at zero degrees advance, dynamically set the timing.  I am almost out of adjustment slot but have this now set to 1.8mm.  To rehash, bike is as follows:

Stock bore 75 350 with DG pipes. Bike has a K&N with a new Y boot.  I have the carb currently (set up with Dave F mod)5DP7 jet needle, 169P0 primary needle jet, 27.5 pilot, with 200 mains and the needle clip in center position, air screw 1 turn out from seated. I took the bike for a ride and is crisp but breaks up at around 5500 rpm really bad and I cannot rev thru this.  I then installed new coils today and BH8S Resistor plugs per below (John from Economy)

Replacement Ignition Coil Kit - for Yamaha RD/R5/YDS6/7. Every thing you need to replace your coils, plug caps and ignition coil wires. Kit Includes the following:
2 Replacement Coils, same dimensions as stock coils, same bolt spacing. Easy to mount and install.
2 NGK 5K Resistor Spark Plug Caps
2 Feet of high quality Ignition Coil Wire[/b]

 With the new coils, it still breaks up at same point.  I did have to repin the gender of the yellow and black wires from the kit as the black was a female connector and the yellow was a male connector as opened from box.  The kit came with crimp on connectors and I replaced, these are now pinned to hook up.  I have changed every ignition part, plugs and coils and have a solid battery that charges around 14.2 volts at 2kRPM.  it seems electrical and does not appear to be running out of gas (just a guess), but just getting bike sorted and don't want to change too many items at once.  Was wondering if my pilot jet needs to go to a 30, would this help the mid transition range?  At a loss for now.  Also, had a question regarding plugs.  With the new coils is a 5K ohm cap.  I am running resistor plugs, I am assuming this is the correct setup. Bike starts first or second kick , idles at 1500 rpm consistently but cannot rev past this point, can only swap gears to drop RPM and then rev to this point where it breaks up. 

Just putting my ignition on this AM, taking a little longer as I fabricated a Y block connector for ignition power verses the scotch lock connector supplied with kit. my question is after installing and verifying "center" on the magnetic trigger that attaches to the rotor, what torque do you put on this?  Also, was thinking of putting on blue removeable loctite (small amount) on the bolt.  wanted to get opinions on this.  Thanks, Brian

I have a 75 350 with Dave F Mod ((with 200 mains, 5DP7 jet needle, 169P0 primary needle jet, 27.5 pilot, air screw 1 turn out and needle clip in center position), DG chambers, Y boot with K&N, stock ignition timed currently at 2.0 (will change soon to 1.8), everything else is stock.  My question is I have the mid range bog that I hear about often (right around 5.5 to 6 K) and wanted to know if a Banshee intake with crossover tube would help with this.  I have not performed a plug chop test yet, just had it running and am on vacation relaxing thinking what I could do when I return.  I have a long hill near my house which will put the bike under a load, was thinking I should pull up on the choke at the mid range bog to see if additional gas helps (which would tell me to jet up a little bit).  Just trying to get my plan in place for when I return next week.  Looking for any constructive input.

Thanks, Brian

Removed and posted in turning wrenches

Hi All,
I searched the forum for some definitive answers to my question and nothing detailed, so here goes.  A few years back I posted an article when I had my last RD (73 350), then sold it and am back in the game after selling my stash of spare parts.  I was running NOS NGK B8HS plugs in my bike without issue, everything that I see now seems to be a resistor type plug from NGK and sources online.  I have a stock ignition (soon to be upgraded to a Dyna S) with stock coils.  When rebuilding, I checked resistance of coils and within spec, and I believe the NGK caps that are on these coils add 5K resistance.  My question is what is the appreciable change from my old b8HS plugs (I actually have 2 left) to running a plug that is a resistor type? I ask as I like to have 2 new plugs in my tool kit so I don't get stranded with a fouled plug (happened in high school on my mint 70 purple and white R5, good thing is that I broke down in front of one of the prettiest girls in schools house and she let me keep it there for a few days till I got it sorted)  Regardless, if anyone could shed some light on this or pros/cons would be much appreciated.  Thanks

I purchased a 75 350 late March (stock bore, someone had put a set of DG pipes on it, stock carb and jetting).  Before tearing into, I put a new battery in it, had spark and then performed a leak down test.  Passed the test (lost 1 psi over 6 minutes), a little tired but will tear into this winter. I put a boroscope in the plug and exhaust hole, little carboned up and some scratches but it sealed and held pressure, again will address this winter  I freshened up the bike with new tires/tubes/rim strips,chain and sprockets, rebuilt caliper, new master and brakes put new rubber and cables on it, rebuilt the carbs and performed the Dave F carb mod (with 200 mains, 5DP7 jet needle, 169P0 primary needle jet, 27.5 pilot, air screw 1 turn out and needle clip in center position).  Upon first trying to get it to run, would backfire thru exhaust.  I reset the factory points to .013" and after swapping the coil wires (found out that the laminated wiring diagram I have has the coil wires reversed),it fired on first kick. Smoked a bit but finally warmed up some and idle settled down to about 1200 rpm, I timed it with a light at 2.00mm. and then started to turn the airscrew out to 1.5 turns each, rpm a little higher when I did this.  The bike is just flat,does not want to rev and I noticed raw gas coming from exhaust when I shut it off.  It has the factory airbox, although a UNI foam filter within that is oiled.  I removed the carbs, and dropped main jet to 190, moved the needle clip up 1 space (2nd from top) and checked the float levels, these were a little high so reset to 15mm.  Put it back together and a little better, but not much.  Definitely not rideable.  I do have a new Dyna S ignition coming today, wanted to get it running with points before I put this on. Looking for some suggestions.  When apart, checked the coils and within spec (original) and put in new plugs before trying to run.  Thinking airbox may be too restrictive, thoughts?  Plans are to bore and mildly port, leave everything else "as is" as this is just a cruiser for weekend runs thru the park and scare the wild animals. 

Just putting bike back together ('75 350) and awaiting final parts from Economy so I can have running by next weekend.  I found that my turn signals are not working, but worked previously before teardown. The stop light on the dash also blinks via the light checker, but this is a bad stop light bulb which is on order.  I have ensured that everything is wired correctly and the laminated color diagram from Evan was a great help.  The flasher gives an 'audible noise" when turned on but does not blink.  I have checked continuity between the wiring connections, all sound and the bulbs are all good.  It appears that the flasher's common wire is via the switch (brown/white) and the brown wire is "hot" as it comes from the regulator.  My gel cell battery is a little low on voltage 11.2, and am thinking that this may be the issue as the bi-metallic switch within flasher is not getting hot enough to snap. I will charge my battery this week and then retry, just wanted to get some opinions for members on best method to troubleshoot the flasher.  I was thinking  maybe hook up switch  to a low current battery charger and check the brown/white wire for voltage or no voltage as referenced against the body or case? (as this is removed and on workbench).  Also, the little ground wire with spade terminal was tight and clean. Thanks, Brian

Hi All,
I am putting my bike back together ('75 350) and utilizing the cable and wire routing diagram from the manual, wondering of anyone has some detailed pics.  The older I get (and with eyeglass cheaters and blowing up the screen) still difficult to read.  I believe the pics in the manual documentation are R5 related and from research here and on the Aircooled RD forum, seems to be a difference between this and the later RD's.  The pics I took during disassembly are not detailed enough, hoping someone had some so that in future, others could reference too.  Thanks in advance, much appreciated if anyone could share a few.

Thanks, Brian

I have a question regarding a leak down test.  I bought a kit from Vintage smoke few years back and have misplaced the instructions with respect to pressure drop over time.  I searched this site, but did not find anything definitive regarding values.  I have a 75 RD350, wanted to know if anyone could provide pressure, acceptable drop over "X" minutes.

Thanks, Brian