Re: Hero Moto Splendor/Joy/CD-Dawn/Passion


Hello members of this Wikipedia of a thread.
Have been a silent reader of this thread from many months. Bike was mostly with my brother. After 5 years and 4 months, the bike has completed 45000 kms.

[MENTION=81267]pranab[/MENTION], after reading your post , out of curiosity i tried to check the insides of a spark plug. So picked up an old dead spark plug, but couldn't get it to open, i even tried heating the ceramic part. Any tips and details on how you managed to open the spark plug.
[MENTION=28527]sibun[/MENTION], a few pages back you advised about changing the air screw after the bike has done 30-40k kms. So thinking about changing it. What is the part number and cost of air screw of Passion Pro ? And are the air screws of Splendor, Passion, CD Deluxe. etc. same or different for each bike ? Also, need to change the steering racer set, should i go for OE or any other ?
Thanks.

Re: Hero Moto Splendor/Joy/CD-Dawn/Passion

In this illustration , the plug with chocolate brown colour ( left ) is burning optimal mix , the white one the right is lean and center one with black carbon is rich .

But in your case you should forget about these pics and tuning the carb . Carburetor's job is to allow finely atomised petrol + air mixture into the combustion chamber during engine suction . Under no circumstance should it allow liquid petrol into it . In your case you have observed plug wet with petrol - so your carburetor is doing something it should not - i.e malfunctioning . There is no point in trying to tune a malfunctioning carburetor . You cannot correct air-fuel ratio while liquid petrol is getting in there .

Because liquid petrol only burns partially , there is lots of soot on your plug . But there is not enough petrol in atomised or vapour form which would burn readily - so the mixture remains quite lean , giving you a white plug . Also engine temperature shall be high and fuel mileage poor .

What I suspect is some of the carburetor's jets or passages are either clogged , or deformed by poking with hard pin ( which mechanics often resort to ) . So instead of releasing atomised spray of petrol during engine suction , it's basically squirting liquid petrol . You have to check and correct this condition first , then tune for an optimum mix and check plug colour .

But remember , this is all my analysis from hundreds of kilometers away from your bike - and I may be all wrong too

Re: Hero Moto Splendor/Joy/CD-Dawn/Passion

Thank you so much Pinaki sir for your help. I will definitely take out the carb and clean it.

Re: Hero Moto Splendor/Joy/CD-Dawn/Passion

Curiosity is good but kindly make sure you dont hurt yourself brother. I have found that dismantling Champion spark plug is very easy. You just have to put the spark plug upside down into the box wrench and heat the metal part of the spark plug (the part that goes into the plug cap). Dont heat the ceramic because it is the insulator. Only heat the metal and hold the plug with the help of box wrench. Try unscrewing the metal part with the help of a plier. If heated properly it will get unscrewed. Inside you will find a spring and a resistor. Keep the spring inside the plug and you can put a small piece of Solid Core Copper wire inside it and screw back the metal part of the plug. Make sure you measure the copper wire perfectly so that it touches the central electrod and the metal part of the plug. Now you have a spark plug with zero resistance. Dont hurt yourself brother while doing this. I did this because i wasnt able to find Bosch U4A model in the market. Everywhere in the market champion spark plug is available including SVC.

These days am not getting spare time to do anything on my bike due to tight work schedule so just following you guys before going to sleep. Tappet adjustment, Carb cleaning is on my todo list.
Pinaki da I agree with you. The brick coloured plug looks to be best AFR mix. I use to get that kind of spark plug when my bike was younger and was running on factory tuned carb. I use to get fantastic mileage aswell and throttle response was crisp.

Re: Hero Moto Splendor/Joy/CD-Dawn/Passion

Completed 38,000 km and counting.

Re: Hero Moto Splendor/Joy/CD-Dawn/Passion

One small query. What is the actual part of the spark plug that should be inspected to check the condition of mixture?

Is it the the part that is like white plastic which surrounds the center electrode?

Or it is the metal part (Dont know the exact name. Pardon me) that is curved above the center electrode and has the gap between the electrode and it?

I am asking this because while going through the old posts in this thread, I found a post by paul.1911 around page 180 where he oberved light brown colour on the metal part that is curved. While white part that surrounds the electrode was complete white.
But till today I thought that the plug is inspected at the white plastic part which turns light brown when running optimal mix.
So please tell what is the actual part that is inspected.

Re: Hero Moto Splendor/Joy/CD-Dawn/Passion

[MENTION=29030]Pinaki[/MENTION] sir- Sir please delete some mesaages from your inbox. I need to send you a PM

Re: Hero Moto Splendor/Joy/CD-Dawn/Passion

Recently, it has been noticed that my Splendor+ fuel meter has been behaving erratically.

Yesterday, it was showing near half of the red section.
Today, it shows around beginning of the Yellow section.
Two week ago, it was not moving upon putting on the bike.

How, is this happening?
Which spare should be repaired / replaced?

Experts, please throw some light on the condition.

Re: Hero Moto Splendor/Joy/CD-Dawn/Passion

[MENTION=68316]dude_creative[/MENTION]:

I want to buy this one.
I asked about this in Fancy Stores and also in Hardware shops. They have no idea about it.
Please tell me where can we find this? did you buy it on online or in which shop you bought it.

----consecutive posts auto-merged-----

What I can guess:
1. Loose Wire connection: Under your fuel tank there will be a wire connection for your Fuel Sensor. Please check if it is loose
or wire is not connected properly.

2. Fuel Unit Sensor is not working: Inside the Fuel Tank there will be a FUEL LEVEL MEASURING UNIT which looks like flush
floater. This unit actually passes the fuel level to the sensor which we can see in the Fuel Meter.

I actually don't know how to identify if the fuel sensor is not working. Below is the pic of Fuel Unit Assembly.



Please wait for more suggestions from experts.

Re: Hero Moto Splendor/Joy/CD-Dawn/Passion

Part 1

Open right side panel .
Above / Beside battery there is a white 2-4 pin connector , traces to fuel gauge assy.
Clean it and check.
IF Problem resolves then stop ELSE part 2

Part 2

Switch on ignition , dont start bike .
use a hanger or any bent metal rod to GENTLY RAISE FLOAT in fuel tank , and see if meter is showing results accordingly
IF Problem resolves then stop ELSE part 3

Part 3

Meter Assy needs to be opened and two resistors in fuel meter need to be changed or new fuel meter to be put in its place.

Re: Hero Moto Splendor/Joy/CD-Dawn/Passion

Sirji since this brownish colour seen on plug is inter-related to throttle position, it also can be in some way tied to the economy range of 30-50 kmph highlighted on speedometers.
So what im trying to ask is that, is the 30-50kmph green zone given, because most optimal firing ecu map naturally have a medium ( not too rich/lean) afr in this zone or do they calculate on basis of estimated throttle position at these particular speeds ?

Re: Hero Moto Splendor/Joy/CD-Dawn/Passion

Search UNIVERSAL BOTTLED JET SPRAY in e bay India


I bought it from roadside shop. should not cost more than 150

Re: Hero Moto Splendor/Joy/CD-Dawn/Passion

When this engine was designed and put to manufacture by Honda sometime in the early 1970s electronic ignition maps and control units were distant dreams . All it had for firing control was the points contact-breaker like this .
Courtesy - Dan's Motorcycle Repair & Engine Repair Information Guide
It's the round plate you see on the engine head surrounded by green gasket material , in this pic you see an Honda C90 engine points under adjustment with a continuity light while the crank is being turned with spanner . It's a mechanical device that advances timing according to rpm . Nothing to do with AFR or the carburetor which must have been adjusted to match manually . The CDI ignition system we have on our bikes , is a direct replacement of this points-contact ignition and a close approximation of it . They just found the engine performance & fuel-efficiency to be optimum in the 30-50 kmph range during testing, I think

Re: Hero Moto Splendor/Joy/CD-Dawn/Passion


Thank you very much for your info.

I will keep you posted on this when I get a new one.

Re: Hero Moto Splendor/Joy/CD-Dawn/Passion

@pranab,, thanks brother. You are right regarding safety. Will keep that in mind for sure.


Everyone, I am wondering if a digital non-contact inductive tachometer is available in our country. Googled this, but didn't get much help. Has anyone come across it ? Any idea about cost ? We have Sibun brother's brilliant carb tuning guide, so this kind of tachometer would be really helpful in knowing about rpm during tuning. So, any ideas ?
Also, most indian bikes now come with CDI ignition if I am not mistaken. But some bikes like Apache RTR come with IDI ignition. So, will the above said tachometer work with all kinds of ignitions like CDI, IDI, &/or others ? Or will it work with some particular kind of ignition ?