DIY: Homemade timing tool

[Quicklimegirl]

In a quick answer... Mark replied in brief. 

In order for me to understand all the hoopla, I need facts, Was the engine bored with new pistons?
What brand and what clearances were used? How big is the bore now? As you go to the much larger bores I add clearance to the now thicker and heavier pistons and never stock clearances in the OEM manual unless your going to run fuel you DON'T buy at any unleaded street pump.
Oversized pistons can drive up the stock compression really high after 1mm over.

Carb jetting we used just several years ago now seem a bit too lean if run too hard.

  Thanks so much, Mark and Chuck.  It's good to be back, but not for this reason!

All new top & bottom end: ProX pistons @ 65.5mm, clearance s/b whatever those call for.  How much additional clearance do you suggest with that oversize of pistons, Chuck?  Perhaps that was the issue, using the standard ProX clearance??
Bike was nearly empty when we took off. I didn't want to put very much non-ethanol in, I don't like to run it at all, but to get to the Amboy where there is non-ethanol, I put in maybe one gallon.  The bike wasn't run hard, never did more than 40mph as I was trying to get used to it again.

This board is invaluable with guys like you and Mark giving me all the stuff I need, it's much appreciated!  What's keeping me from wrenching now is severe arthritis, my fingers & hands can seize up worse than that engine with too much gripping, but I might just tackle the RZ or my custom RD next, minus the boring and crankshaft work.

I can't really spring for a more modern ignition, assuming the module on this one is still okay. I've already spent more on the bike than I thought it would be, so I hope the ignition's still good. 

Thanks again guys.  If it wasn't raining right now I'd go for a spin on the HS1 or RD125. I need to hear more ring-dinging!

[paul1478]

Video here.

https://imageevent.com/supertune/paulsrd400?p=249&n=1&m=-1&c=3&l=0&w=4&s=0&z=3
[/quote]

ahhh back when my bike ran. how I miss it!

[SUPERTUNE]

In a quick answer... Mark replied in brief. 

In order for me to understand all the hoopla, I need facts, Was the engine bored with new pistons?
What brand and what clearances were used? How big is the bore now? As you go to the much larger bores I add clearance to the now thicker and heavier pistons and never stock clearances in the OEM manual unless your going to run fuel you DON'T buy at any unleaded street pump.
Oversized pistons can drive up the stock compression really high after 1mm over.

Carb jetting we used just several years ago now seem a bit too lean if run too hard.

  Thanks so much, Mark and Chuck.  It's good to be back, but not for this reason!

All new top & bottom end: ProX pistons @ 65.5mm, clearance s/b whatever those call for.  How much additional clearance do you suggest with that oversize of pistons, Chuck?  Perhaps that was the issue, using the standard ProX clearance??
Bike was nearly empty when we took off. I didn't want to put very much non-ethanol in, I don't like to run it at all, but to get to the Amboy where there is non-ethanol, I put in maybe one gallon.  The bike wasn't run hard, never did more than 40mph as I was trying to get used to it again.

This board is invaluable with guys like you and Mark giving me all the stuff I need, it's much appreciated!  What's keeping me from wrenching now is severe arthritis, my fingers & hands can seize up worse than that engine with too much gripping, but I might just tackle the RZ or my custom RD next, minus the boring and crankshaft work.

I can't really spring for a more modern ignition, assuming the module on this one is still okay. I've already spent more on the bike than I thought it would be, so I hope the ignition's still good. 

Thanks again guys.  If it wasn't raining right now I'd go for a spin on the HS1 or RD125. I need to hear more ring-dinging!

Q,
For Pro-x at that bore size of 65.50 size .0025-.0026
Forged pistons would be .0033-.0034
C

[scully]

I use what ever the pump puts out at any station........air leak or really bad timing. Thinking air !

[paul1478]

Not Homemade, but I've used this little gem with great results. You don't even have to remove the tank.

Can't seem to locate the eBay listing where I purchased it, but it's identical to the "Buzzetti Micrometer Timing Tool".
Mine isn't branded, and I only paid like $20-25 for it. So I'm sure if you hunt around you can find one cheaper.

I know this is old but I just ordered this item to check my timing. My bike seems down on power the last 2-3 outings. I had to rebuild once due to slipped timing and do not care to do that again.
Can someone tell me what the best (or easiest) method to tell when the timing is triggering (I have the vape system)? Listening for the sparkplug fire (out of the hole grounded in the bike) using multimeter?

I also plan on checking everything else this weekend, head torque, plugs, air filters. Check for leaks using something to spray at the posable air leak points.

Thanks for any suggestions on the checking timing... 

[m in sc]

with a vape? timing light. gauge to verify marks, has to be running to verify. 

[paul1478]

can I just find 1.9MM BTDC and verify it is sparking by moving it into this area? It was sent right by Chuck for sure. I want to be sure it did not move. I do not own a timing light, I can get one if I really need it.

[m in sc]

it needs to be spinning  to charge the primary coil to fire the ign coil. buy a timing light..?  they aren't that expensive.

[paul1478]

Thanks Mark. Do I not need a timing light that works on 2 strokes ?
Any inexpensive suggestions?

[soonerbillz]

I've used this for a thousand years to do everything from TDC to crankshaft runout and all other myriad or measuring.
It always took some figuring setup..on making mounts. But works perfect every time.  It cost a bunch back then..but now they are ebay cheap..

[paul1478]

What is the model or manufacturer?
I would like to look for one.

[dgorms]

Ahh......... Starret! I inherited some Starret and Mitutoyu machine tools from my cousin, still haven't figured out all you can do with them

[m in sc]

any timing light will work.  i have one of these, it works really well and does have a 2 stroke mode.  https://www.summitracing.com/parts/anm-cp7529

[soonerbillz]

What is the model or manufacturer?
I would like to look for one.

If you are asking what dial indicator I posted.. it's a model 196 Starrett.
You can find the indicator alone pretty cheap online.. and there are cheap Chinese knockoffs too. But to be honest you really need the other parts in my kit to make it precise.. really helps.
I use a old compression tester that I modded to screw on the clamp. The ball rod slips down the hole into cylinder... works well.

[m in sc]

https://www.economycycle.com/shop/yamaha-rd250350400r5ds6ds7-parts/electrical-ignitions-lighting/ignition/central-tools-dial-gauge-timing-kit/


worth it.