My Red Yamaha RX 100

[anjan_c2007]

While the RX100 is under repairs, I have this news to convey.Its kudos to the RX 100 engine block.The engine block and piston were checked at another workshop using lathe machines for probable damages by my mechanic.
ITS HATS OFF AND A TRIBUTE TO THE YAMAHA BIKE MAKERS - AND MARVELLOUS NEWS FOR ME TO KNOW THAT THERE WAS NO ENGINE DAMAGE OF ANY KIND WHATSOEVER.20 years on and still lugging.
The same piston and engine block are being now reassembled on the bike.However my mechanic has expressed his apprehension with the piston rings and so the rings and the gudgeon pins are being replaced.
Thankfully, the YASS did not have a new engine block available or else would have had to return that and a new piston back.I have not bought even a new piston as my mechanic was always saying that only after the engine block is checked should we venture for engine spare purchases.

[rxpaul]

Hi Anjan,
On Dec 20th I took out my RX from its wraps, got the carb cleaned, changed the spark plug and had it washed.

Plan to get it painted and chrome plated.

Anjan, Just before your bike seized, did you get any change in pickup or sound ?

[(Alok)]

Originally Posted by anjan_c2007

THAT THERE WAS NO ENGINE DAMAGE OF ANY KIND WHATSOEVER.20 years on and still lugging.

Congratulation
I can feel your feelings.

Originally Posted by anjan_c2007

The same piston and engine block are being now reassembled on the bike.However my mechanic has expressed his apprehension with the piston rings and so the rings and the gudgeon pins are being replaced.

Can you please explain that how we can understand ring upsizing? I mean as you are going for new rings, defiantly these are of higher dia. Please post the pics of older and newer rings showing code/ number embossed on them.

[alok_balsekar]

[quote=(Alok);2195271
Can you please explain that how we can understand ring upsizing? I mean as you are going for new rings, defiantly these are of higher dia. Please post the pics of older and newer rings showing code/ number embossed on them.[/QUOTE]

@(Alok) it is not necessary to put in an oversized set if the engine has not seized (and not "ceased" as most noobs would say LOL).

Normally , any engine reassembly would merit a change of rings. We don't do that due to cost / availability of spares.

Also if oversized rings are to be put in ONLY in conjecture with a rebore and the next oversized piston.

[anjan_c2007]

Originally Posted by alok_balsekar

@(Alok) it is not necessary to put in an oversized set if the engine has not seized (and not "ceased" as most noobs would say LOL).

Normally , any engine reassembly would merit a change of rings. We don't do that due to cost / availability of spares.

Also if oversized rings are to be put in ONLY in conjecture with a rebore and the next oversized piston.

Thanks Alok nicely said.

Originally Posted by (Alok)

Congratulation
I can feel your feelings.
Can you please explain that how we can understand ring upsizing? I mean as you are going for new rings, defiantly these are of higher dia. Please post the pics of older and newer rings showing code/ number embossed on them.

Thanks Alok for your congratulations. Actually the new ring that is to be fitted in my bike is of standard size with the original piston of OE dimensions.This is because there was no reboring involved.
Once the engine (any engine for that matter) is rebored and depending on the quantum of damage the engine bore is increased by 0.2 oversize if the damage is minimal.
Next if the damage is of a greater magnitude the oversize (rebored) is 0.4.
I am not sure about 0.6 oversize but after reaching a limit, the engine block needs to be changed and the standard bore is then applicable with standard sized piston and rings.
The manufacturer has pistons and rings for upto 0.4 oversize, sold through their respective company spare dealer or these are available with most spare part dealers.
If reboring is done the bore diameter increases and so also the requisite piston and rings (usually two rings for each piston).
Will post pictures soon.

Originally Posted by rxpaul

Hi Anjan,
On Dec 20th I took out my RX from its wraps, got the carb cleaned, changed the spark plug and had it washed.

Plan to get it painted and chrome plated.

Anjan, Just before your bike seized, did you get any change in pickup or sound ?

rxpaul all the best with your restoration job for the RX 100.
I did not feel any difference in the pick up or sound of any perceptible kind.The only fault was that it had developed starting trouble because of some kind of dryness that had caused the engine and its components to starve.
Had the engine and piston damage been significant with compression loss I would have certainly felt a drop in the pick-up. Luckily the damage was caught in its infancy- like some benign ailment.

[anjan_c2007]

So finally my red warrior is back home safe and sound after its sojourn at the workshop for nearly a week.The work has been done satisfactorily. I drove it back and the street was crowded - so no fourth cog engagement for longer durations.The whole bike feels like new and I really feel nostalgic. Maybe its flashback 1990 when the machine was new. The engine response is awesome in response to the throttle engagement.With the new clutch, the gear shift requires me getting a bit used to. The first is OK but the neutral comes and stays on and bypassing it to reach the second cog needs efforts.The second to third and third to fourth shifts are also a bit effort requiring. But the acceleration and engine performance is smooth and effortless. Henceforth I shall be adding engine oil to the petrol tank and the engine shall also get oil from the pump.It wont go hungry at least now as double oil is recommended for at least 1000 plus kms of run. It was dark and so no pictures now. Shall be posting them this weekend hopefully.

[anjan_c2007]

Its been nearly a month since the RX100 was back on its wheels.I have sparingly used it and find the ride quite OK. The new clutch, engine bearings and crankshaft plus the other engine spares replaced and the engine decarbonisation job have improved the bike's performance.Its not extremely free revving though till now.I am also taking care not to exceed 50 kmph in the top gear till the engine runs at least about 500 kms and am adding 2T oil in the petrol tank too, as the oil pump has limitations and the engine needs some more oil for the new moving parts..The oil pump is brand new though.
The first-neutral-second gears are a bit harder and need to be engaged with some more effort.The person who repaired my bike is out of station now and will be back soon. The gears will be then given a check.

[anjan_c2007]

The RX 100 had a nagging clutch adjustment problem.It was traced to a missing small ball bearing that is located on the aft side of the clutch connecting needle.This needle can be accessed by opening the left side cover, which opens after the gear lever is dismantled.With the tiny ball bearing not in its place , the clutch adjustment can turn into a nightmare.

I also got a brand new Amaron battery fitted to the bike. The old one of Exide make had been there since 2007 and was doddering.This new one has cost me Rs 845=00 and after exchanging the old one, it was Rs 61 cheaper viz @ Rs 784=00.
So again the RX 100 is back on its two wheels.I was not using it since many weeks.But today it has been made fit and will run on and on hopefully. Touchwood!

[anjan_c2007]

Must say my Yamaha is doing fine and is now in perfect running condition after the January 2011 major engine job.
I have fitted a rubber cover on the side stand lower end.The side stand lower end is dangerously designed and can hurt the feet.I do not know how the Japs designed such a side stand as we in India wear chappals, Hawaii slippers and sandals.Mountaineering boots must be used to escape getting injured!
The rubber cover is borrowed from the Mahindra jeep's rear folding seat.It does the cushioning job here to keep the seat lever ensconced with the jeep's metal floor.
This is just fine for use in the side stand and costs Rs 20=00.There is an original cut at its base, which can make it fit varied configurations of a side stand. I have used a G.I. wire to hold it tight, but two suitable hose pipe fasteners with nuts and bolts will also do the same job and look more aesthetic.

The rubber with its base cut.

The sharp edges seen here are prone to hurt the foot











And below are some pictures of the new side panels and the front monogram.

[SriramEfunds]

Originally Posted by anjan_c2007

Must say my Yamaha is doing fine and is now in perfect running condition after the January 2011 major engine job.
I have fitted a rubber cover on the side stand lower end.The side stand lower end is dangerously designed and can hurt the feet.I do not know how the Japs designed such a side stand as we in India wear chappals, Hawaii slippers and sandals.Mountaineering boots must be used to escape getting injured!
The rubber cover is borrowed from the Mahindra jeep's rear folding seat.It does the cushioning job here to keep the seat lever ensconced with the jeep's metal floor.
This is just fine for use in the side stand and costs Rs 20=00.There is an original cut at its base, which can make it fit varied configurations of a side stand. I have used a G.I. wire to hold it tight, but two suitable hose pipe fasteners with nuts and bolts will also do the same job and look more aesthetic.

Thanks for sharing the idea of fixing the rubber part of Mahindra Jeep on to the RX side stand. I've been a victim many times on my bike.

I have my RX135(4s) fitted with 5s centre stand for the effortless drawing the stand at parking. Call me stupid or dumb, somehow the centre stand gets hit on the chain drive and have scrapped paint over the period of time even that is pardonable. But the worst part the stand hits hard with a loud bang. For some knowledge defficiency reason, could not figure out if that 4 speed and 5 speed design different or was something wrong with the way it has been plonked.

You suggestion sparked an idea to try this out if this could be solution to centre stand issue.

[superlux]

These are some pics of my 1989 RX 100. It has been my companion for the last two decades. I was thinking of getting it repainted (first time) and give a golden hue to the spokes ( like the MV Agusta F5), paint the rims and chain guard buff black as also the front shockers. Any suggestions?

[anjan_c2007]

One year is over after the engine cranking to its destruction and needing an overhaul job.The bike runs OK now and feels like new with the jobs done.It was 3M day today for the bike and it was given TLC with 3M Plast Shield and Tyre Shield.Polishing was done a few weeks back.These products with the polish do a fine job and bring freshness to the machine.Locate any plastic part be it the speedo console,the clutch wire cover,mirrors,headlight console, indicators, the seat cover too and so on.The Tyre Shield is use don all rubber parts. Tyres,mud flaps,rubber cover on the lever end of the clutch and front brake and so on can be coated with the Tyre Shield! The surfaces emerge like new!

[Ajaybiz]

Bike has just 7K on odo meter or you have done 1L 7K kms?
Anjan sir keep the old block running till it reaches its end at 1 mm over size and dont fall for new available bores at Yamaha showroom, they are cheap Taiwan imports not at all at par with OE cylinders.
Even after reaching 1 mm over size you'll have the option of going for RX115 cc standard piston which is available as 5th and 6th over size.

[anjan_c2007]

Originally Posted by Ajaybiz

Bike has just 7K on odo meter or you have done 1L 7K kms?
Anjan sir keep the old block running till it reaches its end at 1 mm over size and dont fall for new available bores at Yamaha showroom, they are cheap Taiwan imports not at all at par with OE cylinders.
Even after reaching 1 mm over size you'll have the option of going for RX115 cc standard piston which is available as 5th and 6th over size.

Thanks Ajay for the valuable suggestions.The speedo console was fully changed about 5 years ago.The 7K plus kms is the running since then- perhaps 2006(will check out the cash memos). the old console had become dull grey and the speedo had RAJDOOT written on the place where YAMAHA is written now. The old speedo did some 44,000 kms. So the total is about 51,000 plus kms as on date.I use the bike once in a while now.
The block did not have to be rebored this time around, so the standard piston is doing its duty. But in case any reboring is needed in future, your suggestion will be helpful.

[anjan_c2007]

Took out my old 1990 RX 100 for a spin today after a long, long time.. It feels awesome to drive and still commands a road presence.
Lately, there was leakage of fuel from its carburettor. I changed the float pin from the ASC for Rs 342=00 within a very short span.It was changed about three years ago.
The float adjustment was actually the culprit.The float adjustment with the pin to remain afloat at its optimum position needs a lot of skill. Even a few tens of microns can make a difference. The old (experienced I mean not old in age) ASC mechanic asked me to enquire about a new float and the counter person said it costs something around Rs 350/-. The mechanic then said that he will try to adjust the float tension, using his skill.Thsi he did and asked me to come back if there was more leakage.
Fortunately, there has been almost no leakage, but I have to be cautious not to store more than two litres in the fuel tank.
Some more pictures of the Yamaha now in its 23rd year of service.


Its most aesthetic pose



original paint, but for the brand new side panels

The letters Yamaha appear twice on the seat cover, once on the number plate (using the VIP suitcase alphabets), once above the taillight in chrome and once on the fuel tank! Its Yamaha everywhere

Yamaha 4 times: mud flap,number plate, above tail light and lastly on seat cover



carburettor woes

the bag to its left rear is quite ugly looking ,but is practical

Right rear view mirror (its new) - "Objects in the mirror are closer than they appear", whereas the old left rear view mirror has no such caution notice!