Re: My mighty Yamaha YBX restoration

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Good to see you posting your restoration as promised

Re: My mighty Yamaha YBX restoration

Waiting for more.
I have ybx lying around at home.About 13 years old and 1 lakh + kms on the odo.
Still doing great but is being used rarely.
I take her out for a spin once a week.

Did you do engine rebulit?
Dont know if it is beneficial to do engine rebuilt.If rebuilt engine comes close to new engine i will go for it.


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Re: My mighty Yamaha YBX restoration

Hi Ishwor, nice to see another YBX owner. Yes i got engine rebuilt. Its really worth going for a rebuild. I have run around 3K kms carefully. The engine is as good as a brand new one. But the main catch is to find an experienced mech, because Ybx engine is so complicated. Will upload all pics ASAP.

Re: My mighty Yamaha YBX restoration

YBX was one of the very under-rated bikes of its time. My friend used to have one and he told me that it is so smooth and pulls very cleanly in every gear without any hesitation. Also there was a balancer wheel for the crank to take care of the vibes,which is quite unique for any single cylinder bike. Please post more details and pics.

Cheers

Re: My mighty Yamaha YBX restoration

Yes you are absulutely right. I really dont know why it was not popular. It has many firsts to its credit. It was the first four stroke bike with double digit bhp. Was first to come with a pass beam and push cancel inicator console. As you said, it has a balancer wheel for crank which not only removes vibes, also increases crank/engine rpm. Hence higher engine speed, which was first and unique in india. Will post all the pics.
Thanks

Re: My mighty Yamaha YBX restoration

Nice to read so far Kiran. Would like to know the complete story.

Re: My mighty Yamaha YBX restoration

I am from nepal and have been riding fz.

Allmost all of our family members(we have large family) learned biking on ybx so it has got emotional attachment to our family so is still in our garage.

It emits smoke when rivved hard but when ridden normally runs well and does not consumes engine oil.
It is not on good shape.So thinking of restoring it.

I know a mechanic from yamaha.He has his own workshop and works in the morning,evening and holidays in his garage .
He is experienced one but still i am not totally happy with the way he works.

He has done many engine works but he works in very filthy manner and doesnt use special tools reffered by yamaha.
He fits engine parts without properly cleaning them.

And the real problem is almost all mechanic i have seen work the same way.
I always feel like our mechanics are not educated enough to do proper engine work.

Any way happy to see you working with your ybx.Hope to join rebuilt work by myself.

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Re: My mighty Yamaha YBX restoration

Apart from the YBX125 owners, all Gladiator and Enticer owners would swear by the engine. It's the same engine put in a different manner. Pity that such a performer never got what it deserved.

Re: My mighty Yamaha YBX restoration

@ krishna77, thanks for showing so much interest man. Yes it is the same engine company has put it enticer and gladiator. Infact with lot of refinement. But as the refinement level rises, the raw power lowers !

@ Ishwor go ahead with the restoration, it is really worth. How about genuine parts availability there ? I advice you yo make a list and procure them first. Will include spares list in my next post. BTW what color smoke it is emitting ? White means problem with piston rings, black means carbon deposition on cams, valves etc (as i know).

Re: My mighty Yamaha YBX restoration

Hi all, lets look at the concluding part of the story. Even after 15 years, the bike looked new with minimal scratches. The paint and chrome were intact. So i decided not to touch them and rebuild only the engine.

In the month of october 2014, i decided to restore it to its past glory. So started hunting for oe parts. There i came to know how difficult is it to procure oe parts. Yamaha guys have completely stopped supply of parts for ybx, so i had to search for oe parts with automobile dealers across bangalore !

It was my routine practice to enquire at each and every automobile shop enroute my work place. None of the spares were readily available, so i had to book them against advance payment and eagerly wait for them to arrive ! The process of acquiring spares itself took nearly a month. Later, my job was to find a good mech to do it. This was even more difficult task, as you all know how competant the mechs are these days !

Finally almost all the parts arrived ! I am making a list of spares acquired below, as this may be useful to other members.

1. Rear wheel hub (oe)
3. Rear tyre with tube (Birla, 3.25 18)
2. Engine gasket kit (aftermarket)
3. All oil seal kit (oe)
4. Axel drive (as the old one had uneven splines !)
5. Guide stopper
6. New cylinder piston kit (oe)
7. Chain sprocket kit (oe)
8. New clutch plates with steel plates
9. New battery (Exide)
10. Tail piece (as old one was missing !)
11. CDI unit (india nippon, oe)
12. Wiring harness (swiss, as oe was nowhere available)
13. All control cables (oe)

Engine works carried out

1. Crank resetting with new bearings (SKF)
2. Head decarbonizing with new valves

here are the pics



As the engine assembly began, some parts were replaced viz, rocker cam, timing chain etc.

My mech took 4 full days to complete engine overhaul. Finally the moment arrived for which i was eagerly waiting for ! A petrol bottle was connected and bike was started. It started, but to my utter surprise, there was a knocking sound coming out of engine ! Mech told me to run the vehicle for a week and the sound will vanish. But even after running it for a month, the knocking sound continued. I was totally down.

I literally fought with him and went to some other mech in my area. The new guy found the root cause of it ! It was actually coming from the big gear wheel behind the clutch bell assy. It is called "driven gear ". Again search started for that part and it was nowhere available. He then machined a faulty tooth on it and fit it back. But luckily the sound had gone and it was all smooth and original !

I thought everything ended smoothly, but it was not. Bike was running smooth with lot of misfires ! Again i started to scratch my head as no mech was able to solve this problem. Later i went to an auto electrician, who carefully examined my magnet coil and adviced me to get it enhanced with extra no of turns. I agreed and work was executed. Voila !, after a nice ride and tune, its all original guys ! I said UFFF... and enjoying it again like before.
Some more pics ...






Below is the pic of crank balancer, which takes out crank vibrations for a smoother ride.



Engine assembling in full swing.....



Next day, cylinder and head assembly started




And finally, my baby is ready to race

Re: My mighty Yamaha YBX restoration

Some attachments are not visible.
Wonderfully done BTW.

Re: My mighty Yamaha YBX restoration

Happy to see you complete the task.Enjoy your ride.

Where did you get the petrol bottle bro.I saw such bottle in svc being used to check the mileage.
Tried to buy in market but it was not available.

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Re: My mighty Yamaha YBX restoration

Thanks, i think most pics are not visible. Will put it again.
[MENTION=52305]Ishwor[/MENTION], its a mileage tester and it is most common with all the mechs in bangalore.

Re: My mighty Yamaha YBX restoration

Hi friends, as some of attachments were not visible, i am putting it back again. Lets hope for its visibility this time.
The spares ....





Now some pics of work under progress ....




And now comes the crank balancer....




Cylinder and head work pics ...