section swept

Defo on the LC’s

As oni nou suggests, they may even suggest a better type of bearing for the life it has to lead. Dont buy the cheapest on offer as these bearings take a hell of load in use.

Have you bought the one fitted with air conditioning??⛱

if anything change them now.....old metal becomes brittle and weak in terms of spring. Fit new reeds metal or Boysen type and you will notice better response all through the rev range?‍?

Put ring into bore where piston ring doesn’t normally reach....this is relatively unworn area square up with pistoncrown now measure ring gap. Its not usual to measure between the ring and cylinder wall. There are some good videos to show you how on google.

Thinking overnight on your problem and as mentioned by Dan Williams it appears the engine has lost a signal trigger ie of the two, one is duff so the CDI unit only sees one signal and cannot effectively shape the pulse to give a stable ignition point....bit like a distributor with one half of the contact breaker missing if you get my drift. Quick solution take a reading from the one sensor and then the other they should be near the same. I believe what you are seeing with the timimg light is the ignition max advance minus the retard which would bring the timing back close to BTDC.....its a really cheap system similar to Citroen= 2 sensors for position and a bolt head as TDC marker the Ignition unit then can work out speed and position. ??‍?

We used to fit Boysen Reeds to nearly every Yamaha RD 250/350 LC that we sold, this included DTs and TYs. We opened out the reed block by carefully removing rubber and aluminium from the area immediately beneath the reed, taking care to leave a good sealing edge for the reed. The standard metal reeds if damaged by high revs will break and bits will enter the engine causing alot of damage. As the Boysen Reeds are made from a laminate material they can withstand high rpm without breaking, if they did break they did little damage but you still had to fish all the pieces out. The reed limit plates were adjusted to giving more opening, you’re not supposed to do this but we did and got good results. I used to keep a TY 175 demo reed block on the counter, one side was modified the other not. This made people sit up and take notice, I never showed the LC reed block as I wanted my secret safe until the customer paid for the mods. Air flow was improved by a potential 20% in each tract.

At this stage I would take everything to do with the ignition off of the engine and frame, assuming your customer is ok with this. Obtain all of the specs and readings expected, eliminate all that could be defective before getting the stator rewound. This will ensure you are not wasting money needlessly. When I was in the trade we’d all lurk by the reception door and cherry pick the good jobs, in the case of this one we’d be hiding away or looking extremely busy?‍♂️?

How are you measuring the ring gap?

Timing check would be a good idea!

That breather could be for the carb float chamber....blocked it would cause the fuel in the float bowl to flood the engine or restrict supply.

Right so more investigation needed. Pick up issue, wiring cocked up, what else will put. +90 degrees on the timimg unless someones moved the base.

Good spark and 90 degrees of timing it has to be a sheared woodruff key??‍?

That kind of damage usually indicates....apart from external forces....con-rod misalignment?

Better that it cracked now rather than later on when you run the engine.

See Thats what I said would happen.

I bet thats a beautiful machine to ride too! Everything braced, supported and sorted. I wish I had something like this in my garage???

Oh good god.... now you’ve raised the stakes with sticker colour .....go slower stickers. I’d go with limegreen and beige. Better still reverse print the GG bit so now its a SAG SAG 521 ATEB...of course there will be doubters that will insist its really a 251 with an actual capacity of 119.9876cc but there you go??‍♂️

Are you going to love it ........or.........LIST IT?

Lets all call it a 125 Gas Gas...there thats better already...its an old GG 125...there there...stay boy stay...its an old 125 GG that someone who should have seen this coming shouldn’t have fitted bits and pieces from ebait and Gumteey. So forget year of birth and any sanquine letters that mean naff all. Get shot of it pdq or tear it apart and put the bits in places that are hard to reach....jumble them up for good measure then in a few years time after a few more bikes have adorned yer shed you may have used most ot the bits. Think long and hard about your next post Bunglebmx its all in your hands now....

Like a little sweet watch, how good does that pump look??

I’ve just had cakey ?made with ?duck eggs and very nice it was too...slaver sounds like Hannibal Lecturn

Be certain you put the seals in the right way round too! Gravity works but takes time.....clear tube on slave cyl. nipple, other end of tube in container with a little fluid to immerse tube into. Undo nipple1/2 turn, you should see some fluid movement. Keep reservoir topped up as the levelgoes down and allow about 1/2 a tea cup of fluid to go through. Close nipple try clutch??usually works, but so does the syringe method. Make sure both ports in the reservoir are clear, you should see the master cylinder piston moving passed the larger port opening and closing off.

Steady on oni its just a newbie finding out?We all need our little Zen like moments??‍♂️whats in a few years, months for a really old 125. Bunglebmx obviously likes his JT.....oh god....sorry GT????????

Armed with this info you are now probably able to date accurately its dimise?