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#41
Turning Wrenches / Re: Electrical Woes
Last post by m in sc - October 14, 2026, 05:12:24 PMits a fun phrnomenon when it backfires. my kz w a dyna does it on rare occasion when I turn it off
#42
Turning Wrenches / Re: Electrical Woes
Last post by SmokeAddicted - October 14, 2026, 02:17:11 PMI've sure wasted a lot of time searching for nothing 
Thanks for confirming
Thanks for confirming #43
Haus of Projects / Re: R5 Rescue
Last post by m in sc - October 14, 2026, 12:28:03 PMnice.
bee leery of crank seals etc. they can be replaced w out splitting cases.
i have 2 r5s myself, fun for sure. and the fact a lot of rd stuff swaps, parts aren't bad. look forward to seeing what you do w this.
bee leery of crank seals etc. they can be replaced w out splitting cases.
i have 2 r5s myself, fun for sure. and the fact a lot of rd stuff swaps, parts aren't bad. look forward to seeing what you do w this.
#44
Haus of Projects / R5 Rescue
Last post by TreeFiddy - October 14, 2026, 11:28:35 AMThanks for the add! Wanna document and share my attempt at rescuing a 1972 Yamaha R5 350. Have a quick rundown and will post more pics when I can.
Have been wanting a two stroke street bike since I fixed up an old shifty Vespa recently and found this one local to me for a good deal. Went out to the country and hauled this out of the brush on an old farm. Here's a summary of the condition and what I've done so far.
Front wheel locked up. Rear wheel barely moves. Chain virtually rust welded. No ignition switch. Seat pan rusted out. Air filter disintegrated and air box rusted out. All cables seized. Oil pump seized. No battery harness. No rear blinkers. Tires from the early 80s and shot. Mud, dirt, brush, cobwebs, dust from sitting for at least two decades in that field.
Went around whole bike unseizing stuff with WD40 and PBlaster.
Removed front wheel to unseize it so bike could be moved around. Brake shoes had delaminated and the pads were stuck to the drum still. Removed chain for ease of movement as well. Rear brake in similar condition. Cleaned wheels up and replaced tires, tubes et cetera.
Pulled heads and removed carbon build up from heads and dome of piston. Inspected bores and cleaned up.
Took carbs off, dismantled and cleaned in ultrasonic. Got rebuild kits and replaced gaskets, needle and fuel valves.
Made up a battery harness myself vs ordering and waiting. Got modern reg/rec. Hotwired the ignition. Bought battery. Bought new points. Bought dial gauge. Timed. Used premix since I assumed the oil pump was shot. Kicked and fiddled and kicked and adjusted and kicked.
Noticed exhaust baffles were plugged up so removed temporarily. Kicked and kicked.
Got used ignition switch and ordered a key based on code. Rebuilt ignition switch and rekeyed barrel to match key.
Horn, brake light and blinkers work. Blinkers don't blink and headlight doesn't work.
Kick and fiddle and kick and adjust and kick and kick.
Starts turning over intermittently.
Take a look at oil pump. Clean up in place and douse in WD40. Unseize and get it working. Realize the oil pump and premix is keeping it from firing. Swap out premix to straight uncut premium.
Kick and kick and adjust and fiddle and it finally starts and runs!
Have been wanting a two stroke street bike since I fixed up an old shifty Vespa recently and found this one local to me for a good deal. Went out to the country and hauled this out of the brush on an old farm. Here's a summary of the condition and what I've done so far.
Front wheel locked up. Rear wheel barely moves. Chain virtually rust welded. No ignition switch. Seat pan rusted out. Air filter disintegrated and air box rusted out. All cables seized. Oil pump seized. No battery harness. No rear blinkers. Tires from the early 80s and shot. Mud, dirt, brush, cobwebs, dust from sitting for at least two decades in that field.
Went around whole bike unseizing stuff with WD40 and PBlaster.
Removed front wheel to unseize it so bike could be moved around. Brake shoes had delaminated and the pads were stuck to the drum still. Removed chain for ease of movement as well. Rear brake in similar condition. Cleaned wheels up and replaced tires, tubes et cetera.
Pulled heads and removed carbon build up from heads and dome of piston. Inspected bores and cleaned up.
Took carbs off, dismantled and cleaned in ultrasonic. Got rebuild kits and replaced gaskets, needle and fuel valves.
Made up a battery harness myself vs ordering and waiting. Got modern reg/rec. Hotwired the ignition. Bought battery. Bought new points. Bought dial gauge. Timed. Used premix since I assumed the oil pump was shot. Kicked and fiddled and kicked and adjusted and kicked.
Noticed exhaust baffles were plugged up so removed temporarily. Kicked and kicked.
Got used ignition switch and ordered a key based on code. Rebuilt ignition switch and rekeyed barrel to match key.
Horn, brake light and blinkers work. Blinkers don't blink and headlight doesn't work.
Kick and fiddle and kick and adjust and kick and kick.
Starts turning over intermittently.
Take a look at oil pump. Clean up in place and douse in WD40. Unseize and get it working. Realize the oil pump and premix is keeping it from firing. Swap out premix to straight uncut premium.
Kick and kick and adjust and fiddle and it finally starts and runs!
#45
Turning Wrenches / Re: Newbie squish questions
Last post by m in sc - October 14, 2026, 10:57:47 AMredo it with just 2 pcs of solder crossed as an x. 4 sperate pcs may have shifted.
as far as doweling, the tried and true way is 2 small dowels one fore and after of the bore thru the head gasket. however, on a relatively stock bike its an nth degree that really doesn't matter.
as far as doweling, the tried and true way is 2 small dowels one fore and after of the bore thru the head gasket. however, on a relatively stock bike its an nth degree that really doesn't matter.
#46
Turning Wrenches / Re: Newbie squish questions
Last post by Vintagewannabe - October 14, 2026, 09:59:55 AMQuote from: sav0r (CL MotoTech) on October 13, 2026, 11:04:52 PMI saw your FB post and Ed Toomey was saying 1mm.Do you mean having the holes widened to fit a dowel in them? Or do you mean centering the heads and drilling them for a small dowel that locks them in? I have tried shifting them different directions and swapping heads with virtually no change in measurement.
He's probably saying that because many are a little sloppy and get it wrong once you start dialing it down closer. It's easy to be too tight on one side and that can cause issues.
Probably the best recommendation is to get the doweled so that you get that variance in orientation removed. Thus avoiding a tight spot that's even tighter than what you have.
With the solder I just used about a 2cm piece in all 4 corners. The head was surfaced but shouldn't have been shortened. I think the machinist either took too much off the top or bottom of my cylinder. From head gasket to base surfaces is 4.024 in, and I read 4.030 is ideal
#47
Turning Wrenches / Re: Electrical Woes
Last post by m in sc - October 13, 2026, 11:37:15 PMyes that's actually normal. when the voltage source is cut the field collapses and it will discharge. with points its thru the capacitor. w out, it can spark
#48
Turning Wrenches / Re: Newbie squish questions
Last post by m in sc - October 13, 2026, 11:35:07 PMi agree. 1mm is safe but not nec optimal
#49
Turning Wrenches / Re: Newbie squish questions
Last post by sav0r (CL MotoTech) - October 13, 2026, 11:04:52 PMI saw your FB post and Ed Toomey was saying 1mm.
He's probably saying that because many are a little sloppy and get it wrong once you start dialing it down closer. It's easy to be too tight on one side and that can cause issues.
Probably the best recommendation is to get the doweled so that you get that variance in orientation removed. Thus avoiding a tight spot that's even tighter than what you have.
He's probably saying that because many are a little sloppy and get it wrong once you start dialing it down closer. It's easy to be too tight on one side and that can cause issues.
Probably the best recommendation is to get the doweled so that you get that variance in orientation removed. Thus avoiding a tight spot that's even tighter than what you have.
#50
Turning Wrenches / Re: Newbie squish questions
Last post by m in sc - October 13, 2026, 08:36:46 PMunless it wast cut flat or measured wrong, no. 1 pc of solder for each leg of the x evens the load out on the piston .