A pack of TY175's!

[Lotus54]

I would not have thought of that- good way to get it right.
Those old point systems on the bikes barely worked when working- the early Japanese ones seemed pretty bad (even though rest of electrics were pretty good). At least from what I remember.
I also remember finding bad condensers even when new, plus the capacity had to match requirements.

Hopefully you can find the answer.

[John H]

I was disappointed that I couldn't get both TYs running befor my grandsons had to leave. But with the go kart, quad and one TY, we still had a good time.
After laying out 5 complete TY ignitions I started testing. I also ordered a new condenser and points kit as well as B7ES plugs.
Starting with the condensers I found only 2 that had values in the 3 ohm range. Of the coils tested, 3 were within the recommended range and 2 were dead. One coil tested ok after removing the spark plug cap. These are resistor caps so may be the problem. Setting the point gap at .012 didn't agree with the .070 btdc timing so changed the gap to set the timing.
I installed one complete ignition set on bike #1 and it started and ran well. I then set up another ignition for bike #2 and set the timing at .070 and it started and ran well also. Wow! Now I'm going to spend some time on the RL250. It starts and runs but need a few parts to make it a good runner.

[Lotus54]

I am starting to have problems finding non-resistor sparking plugs. I’ve ordered B7ES and got BR7ES and local parts stores show that B7 superseded to resistor.
A non-resistor cap should solve it if you have the same issue.

[John H]

Is there any performance effects when using a resistor plug? It's petty common to remove the resistor from the spark plug cap and replace it with a copper wire.

[Lotus54]

I have read different things. I believe the resistor setup was originally for RF interference. This can be for radios but also could affect electronics (not much of that on a TY). But I also read someplace that it can help very slightly lengthen spark. I do not know about that or if true at all.

Some systems require it, at least in the documentation. Yes, the old days any resistance was removed, although while some ignitions back then were excellent (like the Motoplat) many were awful. I know the Vape ignition I fit to a couple bikes specifically says to have one resistance component, but do not double them up. So a resistor cap, non-resistor plug.
But at least for NGK (which is what I use most often) it seems many resistor plugs are being discontinued.

[John H]

We were discussing this very topic today on a vintage bike forum. Many vintage bikes had magnetos that were marginal at best. Of course some of their weakness was due to capacitors. Lucas had a reputation of failing for a number of reasons.
If you need, we can clean and test your plugs. Interestingly with a bit of cleaning, filing and gapping correctly some plugs will spark better than new. Not sure what the -11 on the number is but the top does not screw off which affects fitment of a lot of older bikes.
https://www.amazon.com/dp/B001RM89GW?ta ... e=osi&th=1

[John H]

The 2 TYs are running great and hopefully will be running great when the grandsons visit next time.
I have been ignoring this RL250 that came with the blue ty purchase. I was surprised with some fresh gas it started right up and sounds pretty good. Reading some reviews online it seems they were not highly valued for serious riders. Complaints included: too much horsepower, gearing not good, forks at wrong angle and frame was subject to cracking. Apparently this bike hadn't been treated to badly as everything is pretty straight except for a few dents in the tank.It's definitely more comfortable for a taller guy than the TY so I'll keep it as the 12 year old grandson is already 5'-8".

SUZUKI RL2504 Large.jpeg (240.82 KiB) Viewed 54971 times

SUZUKI RL2503 Large.jpeg (298.1 KiB) Viewed 54971 times