xx's Yezdi 250 project

xxaarraa · 18th February 2009, 17:24

Folks,

Just picked up a 1975 Yezdi in semi-decent shape. I hope its OK to start this thread to chronicle my projects and ask for ongoing assistance.

Background: It's a 1975 Model 'B', but is a bit of a mish-mash. RK tank, RK headlight, ODO/ignition unit, RK handlebar, Enfield 350 carb, Enfield switchgear. What more, I plan to make it even more of a hodge-podge with parts I will extract from a donor Jawa.

First project: fix a leak in the left side of the gas tank.

The previous owner must not have had more than a liter of fuel while I test rode so I didn't catch the leak before buying. As soon as I filled it up, the left started seeping fuel. I did a DIY M-Seal job as I intend to replace the tank anyway with the Jawa's.

Second project: Set the right idle.

The bike wasn't idling by design (dead beat?) and I couldn't stand it. Played with the pilot and air screw and got it to idle more or less the way I want.

Third project: check the battery condition.

When I opened up the side case to inspect the battery, I found the positive was completely disconnected. The negative ground was OK. Filled up the battery with distilled water (do they make dry-cell gel batteries in 6 V?) and put fresh terminal clips on and connected everything back up. Here's my question though: how was my bike running fine with the battery completely disconnected? My lights were also working though intermittently. I suspect there is some sort of loose connection in the switchgear. Is there a way to check the health of the alternator? What should the voltage readings be when engine is running?

Still to come.....

Fourth project: replace brake liners front and back

Fifth project: replace RK tank with painted and chromed Jawa tank

Sixth project: replace RK headlight, RK ODO/tach and Enfield switchgear with Jawa equipment. The ignition switch unit I have seems to be faulty or improperly wired. I know that first setting is drive, second is parking lights, third is full lights and fourth is to start from battery. But in my bike, the lights work (sometimes) in first, second and third positions.

Seventh project: fabricate a solo seat

esteem_lover · 18th February 2009, 17:40

Please get the original Yezdi tank back on. Please !!!

Not idling is the way to go in a Yezdi. But it is your choice.

xxaarraa · 18th February 2009, 21:19

Third project update

I think I figured out what's wrong with my electrical system. It may be a dead battery.

I took apart the light switch and nothing was amiss - all wires were properly soldered in place.
I unplugged the battery, started up the bike and turned the lights on. BAM, they shine nice and bright. Alternator must be doing its job.
I plugged the battery back on, started up the bike and turned the lights on. They shine, but very dimly. I am assuming the alternator is feeding most of the juice to charge the battery and only very little is available for the lights.
With the battery plugged in but engine not turning over, the lights come on intermittently. I am assuming that's because the battery has little or no juice and the lights go off and on.
I repeated Step 2 and same result.

I did all the steps with the key in ignition setting 1. Which leads me to believe my bike is directly wired and doesn't have the 4 step ignition setting that it should.

I wish I had my DMM with me, I left it in Chennai last week. Once I get it back next week, I'll hook it up and note down the voltages.

Question: On a 6 V battery, I am assuming voltage at the terminals without ignition should be ~ 5.75 and with ignition on to be about ~7.5v. Can anyone confirm?

Question: How can I go about checking if my Voltage Regulator (VR) is fried? Could it be possible that my alternator is fine but VR isn't doing the job of charging my battery right?

Also, while taking apart the light switch, I noticed two loose wires dangling about (pictures attached). One goes into the headlight doom and another is tied to the ODO/tach unit.

Question: Anyone know what these loose wires are for?

Thanks a bunch.

kuttapan · 19th February 2009, 04:13

The blue dangling wire is for the speedo light. Hard to say what the other one might be.

howler · 19th February 2009, 16:03

thats a flower / porcupine head youve got on, its basically a high compression head, dont ever sell it. fit a jikov carb and see how she flies.

gendarmee · 19th February 2009, 20:39

Please get a flat side Yezdi tank, not a Jawa tank. Also, getting a good condition jawa tank would be more trouble than getting the right yezdi tank. Please replace the headlight with a proper yezdi nacelle. Add a front mudguard change to the list too, if ya plan to get the nacelle as the RK one wouldnt looks appropriate.

-The bike will run and lights will work w/o the battery. The battery is only for the parking lights, horn and emergency ignition. If one wants one can fix a horn that works w/o the battery too. A six volt battery wouldnt charge well, Its probably better to use a kinetic honda's battery.

xxaarraa · 21st February 2009, 12:02

Just picked up a few essential parts:

Brake shoes/liners - 2 sets: 550
Engine bearings + Top gear bearing - 4 numbers (FAG brand?): 700
Main shaft bearing - 1 number (TATA brand): 160
Headlight bulb - 2 numbers: 120
Oil seals - 3 numbers: 160
Engine packing kit (gaskets and crush washers) - 50

I have a feeling the old man charged me too much (I paid only 90 for a set of brake liners for my Karizma versus 275 for the Yezdi). What prices are you all seeing for these parts?

gendarmee · 21st February 2009, 12:26

Quote:

Originally Posted by xxaarraa

What prices are you all seeing for these parts?

Where did you pick up the stuff from?

xxaarraa · 22nd February 2009, 09:25

Anyone know what the best possible plug is for these Yezdis? I have a box of these (Iridium + projected tip) that I use to good effect on all my bikes and wondering if its a good idea for the Yezdi as well:

Interested in opinions, thanks.

Sankar · 22nd February 2009, 10:18

The Yezdi plug is probably a B sized thread, so the D sized (smaller) thread won't fit.

TuffRyder · 22nd February 2009, 22:35

Wow!! Congrats. This is quite a fabulous bike. I hope you plan to restore to its original glory. Your quite lucky that it still has many of the original parts, especially the head and the exhausts. Once your bike is mechanically sound, you should start collecting parts and try to get it as original as possible. You might have to wait for a few months but honestly it is worth the wait.

The things you should look out for: Tank, nacelle (this although similar to Jawa's is not the same), handlebar, throttle unit, levers, front fender, round chainguard (I think the end of 75 they discontinued this), taillamp, and rear shox.

All the best.

smart2smart · 22nd February 2009, 23:52

how much you paid for this bike mate ?
she looks cute....any plans changing the colors ? i guess its not the original color, is it ?hope will fine the right parts to get back her glory
cheers

gaddiwale · 23rd February 2009, 00:03

Quote:

Originally Posted by xxaarraa

Anyone know what the best possible plug is for these Yezdis? I have a box of these (Iridium + projected tip) that I use to good effect on all my bikes and wondering if its a good idea for the Yezdi as well:

Interested in opinions, thanks.

Request you to please visit official Ideal Jawa website (IDEAL JAWA ( INDIA ) LIMITED), surprisingly it still alive. According to the website the right spark plug for Yezdi Classic/RoadKing is Mico W225Z or Modi Champion L82 Yc and recommended gap is 0.7-0.8 mm. I guess the correct eqivalent in NGK is B7HS.
All the best.

gendarmee · 23rd February 2009, 01:10

Quote:

Originally Posted by xxaarraa

.....the battery, started up the bike and turned the lights on.

Check if the rectifier is working, its underneath the seat.

xxaarraa · 24th February 2009, 08:58

I just took some battery voltage measurements using a DMM and got some rather curious readings.

Ignition on, bike not turning over: 8.65V
Ignition on, engine running: 2.31V

Now, it's a 12V battery and only a 6V charging system. That explains the 8.65V. The battery is steadily discharging. Not surprised.

I can't explain the 2.31V while engine is running though. Typically, the alternator/VR will put out more than the max battery capacity to run the electricals AND charge the battery at the same time. Going by that logic, shouldn't the reading have been closer to 8V if the alternator/VR are from a 6V system?

Anyone got any ideas?

18th February 2009, 17:24	#1
xxaarraa BHPian Join Date: Nov 2007 Location: Lot of places Posts: 140 Thanked: 14 Times	xx's Yezdi 250 project Folks, Just picked up a 1975 Yezdi in semi-decent shape. I hope its OK to start this thread to chronicle my projects and ask for ongoing assistance. Background: It's a 1975 Model 'B', but is a bit of a mish-mash. RK tank, RK headlight, ODO/ignition unit, RK handlebar, Enfield 350 carb, Enfield switchgear. What more, I plan to make it even more of a hodge-podge with parts I will extract from a donor Jawa. First project: fix a leak in the left side of the gas tank. The previous owner must not have had more than a liter of fuel while I test rode so I didn't catch the leak before buying. As soon as I filled it up, the left started seeping fuel. I did a DIY M-Seal job as I intend to replace the tank anyway with the Jawa's. Second project: Set the right idle. The bike wasn't idling by design (dead beat?) and I couldn't stand it. Played with the pilot and air screw and got it to idle more or less the way I want. Third project: check the battery condition. When I opened up the side case to inspect the battery, I found the positive was completely disconnected. The negative ground was OK. Filled up the battery with distilled water (do they make dry-cell gel batteries in 6 V?) and put fresh terminal clips on and connected everything back up. Here's my question though: how was my bike running fine with the battery completely disconnected? My lights were also working though intermittently. I suspect there is some sort of loose connection in the switchgear. Is there a way to check the health of the alternator? What should the voltage readings be when engine is running? Still to come..... Fourth project: replace brake liners front and back Fifth project: replace RK tank with painted and chromed Jawa tank Sixth project: replace RK headlight, RK ODO/tach and Enfield switchgear with Jawa equipment. The ignition switch unit I have seems to be faulty or improperly wired. I know that first setting is drive, second is parking lights, third is full lights and fourth is to start from battery. But in my bike, the lights work (sometimes) in first, second and third positions. Seventh project: fabricate a solo seat Attached Thumbnails
	(1) Thanks

18th February 2009, 17:40	#2
esteem_lover Senior - BHPian Join Date: Jul 2006 Location: Madras/Py Posts: 7,556 Thanked: 513 Times View My Garage	Please get the original Yezdi tank back on. Please !!! Not idling is the way to go in a Yezdi. But it is your choice. Last edited by esteem_lover : 18th February 2009 at 17:41.
	(1) Thanks

18th February 2009, 21:19	#3
xxaarraa BHPian Join Date: Nov 2007 Location: Lot of places Posts: 140 Thanked: 14 Times	Third project update I think I figured out what's wrong with my electrical system. It may be a dead battery. I took apart the light switch and nothing was amiss - all wires were properly soldered in place. I unplugged the battery, started up the bike and turned the lights on. BAM, they shine nice and bright. Alternator must be doing its job. I plugged the battery back on, started up the bike and turned the lights on. They shine, but very dimly. I am assuming the alternator is feeding most of the juice to charge the battery and only very little is available for the lights. With the battery plugged in but engine not turning over, the lights come on intermittently. I am assuming that's because the battery has little or no juice and the lights go off and on. I repeated Step 2 and same result. I did all the steps with the key in ignition setting 1. Which leads me to believe my bike is directly wired and doesn't have the 4 step ignition setting that it should. I wish I had my DMM with me, I left it in Chennai last week. Once I get it back next week, I'll hook it up and note down the voltages. Question: On a 6 V battery, I am assuming voltage at the terminals without ignition should be ~ 5.75 and with ignition on to be about ~7.5v. Can anyone confirm? Question: How can I go about checking if my Voltage Regulator (VR) is fried? Could it be possible that my alternator is fine but VR isn't doing the job of charging my battery right? Also, while taking apart the light switch, I noticed two loose wires dangling about (pictures attached). One goes into the headlight doom and another is tied to the ODO/tach unit. Question: Anyone know what these loose wires are for? Thanks a bunch. Attached Thumbnails Last edited by xxaarraa : 18th February 2009 at 21:21.
	(1) Thanks

19th February 2009, 04:13	#4
kuttapan Senior - BHPian Join Date: May 2007 Location: Melbourne Posts: 1,155 Thanked: 27 Times View My Garage	The blue dangling wire is for the speedo light. Hard to say what the other one might be.
	(1) Thanks

19th February 2009, 16:03	#5
howler BANNED Join Date: Aug 2008 Location: coorg/bangalore Posts: 459 Thanked: 606 Times Infractions: 0/1 (10)	thats a flower / porcupine head youve got on, its basically a high compression head, dont ever sell it. fit a jikov carb and see how she flies.
	(1) Thanks

19th February 2009, 20:39	#6
gendarmee BHPian Join Date: Nov 2007 Location: India Posts: 740 Thanked: 32 Times	Please get a flat side Yezdi tank, not a Jawa tank. Also, getting a good condition jawa tank would be more trouble than getting the right yezdi tank. Please replace the headlight with a proper yezdi nacelle. Add a front mudguard change to the list too, if ya plan to get the nacelle as the RK one wouldnt looks appropriate. -The bike will run and lights will work w/o the battery. The battery is only for the parking lights, horn and emergency ignition. If one wants one can fix a horn that works w/o the battery too. A six volt battery wouldnt charge well, Its probably better to use a kinetic honda's battery.
	(1) Thanks

21st February 2009, 12:02	#7
xxaarraa BHPian Join Date: Nov 2007 Location: Lot of places Posts: 140 Thanked: 14 Times	Parts update & price check Just picked up a few essential parts: Brake shoes/liners - 2 sets: 550 Engine bearings + Top gear bearing - 4 numbers (FAG brand?): 700 Main shaft bearing - 1 number (TATA brand): 160 Headlight bulb - 2 numbers: 120 Oil seals - 3 numbers: 160 Engine packing kit (gaskets and crush washers) - 50 I have a feeling the old man charged me too much (I paid only 90 for a set of brake liners for my Karizma versus 275 for the Yezdi). What prices are you all seeing for these parts? Attached Thumbnails Last edited by xxaarraa : 21st February 2009 at 12:03.
	(1) Thanks

22nd February 2009, 09:25	#9
xxaarraa BHPian Join Date: Nov 2007 Location: Lot of places Posts: 140 Thanked: 14 Times	Anyone know what the best possible plug is for these Yezdis? I have a box of these (Iridium + projected tip) that I use to good effect on all my bikes and wondering if its a good idea for the Yezdi as well: Interested in opinions, thanks. Attached Thumbnails
	(1) Thanks

22nd February 2009, 10:18	#10
Sankar Senior - BHPian Join Date: May 2005 Location: Location Posts: 5,784 Thanked: 9,250 Times	The Yezdi plug is probably a B sized thread, so the D sized (smaller) thread won't fit.
	(1) Thanks

22nd February 2009, 22:35	#11
TuffRyder BHPian Join Date: Jul 2008 Location: Bangalore Posts: 494 Thanked: 32 Times	Wow!! Congrats. This is quite a fabulous bike. I hope you plan to restore to its original glory. Your quite lucky that it still has many of the original parts, especially the head and the exhausts. Once your bike is mechanically sound, you should start collecting parts and try to get it as original as possible. You might have to wait for a few months but honestly it is worth the wait. The things you should look out for: Tank, nacelle (this although similar to Jawa's is not the same), handlebar, throttle unit, levers, front fender, round chainguard (I think the end of 75 they discontinued this), taillamp, and rear shox. All the best.
	(1) Thanks

22nd February 2009, 23:52	#12
smart2smart BHPian Join Date: Apr 2006 Location: abu dhabi Posts: 72 Thanked: 2 Times	how much you paid for this bike mate ? she looks cute....any plans changing the colors ? i guess its not the original color, is it ?hope will fine the right parts to get back her glory cheers
	(1) Thanks

24th February 2009, 08:58	#15
xxaarraa BHPian Join Date: Nov 2007 Location: Lot of places Posts: 140 Thanked: 14 Times	DMM readings I just took some battery voltage measurements using a DMM and got some rather curious readings. Ignition on, bike not turning over: 8.65V Ignition on, engine running: 2.31V Now, it's a 12V battery and only a 6V charging system. That explains the 8.65V. The battery is steadily discharging. Not surprised. I can't explain the 2.31V while engine is running though. Typically, the alternator/VR will put out more than the max battery capacity to run the electricals AND charge the battery at the same time. Going by that logic, shouldn't the reading have been closer to 8V if the alternator/VR are from a 6V system? Anyone got any ideas?
	(1) Thanks