I like the Bajaj headset shape but I don't like the speedo surround or the switches preferring Vespa ones which are cheaper and more reliable than the Bajaj ones.
In this page I will be taking you through the task of replacing the Bajaj forks with stock PX forks and what you will need and what you will need to do, you will be surprised just how easy it really is and I hope to take the pain and swearing out of the project for you as well by going through it step by step.
I will say here and now it is not a job for the fainthearted, it looks easy BUT you are dealing with the very one thing that can make or break a safe ride.
Tools needed:
Socket and spanner selection
Straight and cross screwdrivers
Mallet and hammer through flat screwdriver or long thin blunt chisel
Wire cutters
Terminal crimp pliers
Rubber mallet (for lifting the headset off if stuck)
WD40/De-greaser
(Optional) Dremil polishing kit
(Optional) Torque wrench
Items needed:
Grease (good quality one as these bearings are out in the open 24/7)
Terminal connectors
Loom tape or loom heatshrink
Good quality insulation tape
Cleaning rags and protecting cloths for new parts
Complete Vespa headset including pinchbolt, switchgear, speedo, speedo cable, front brake switch, starter motor switch, headlight and bulb holder, bulbs, repeater bulbs and gems if using a MK1 headset top (I would not recommend this as you have no need of a second ignition switch, use the better if you can EFL headset top and the larger speedo with the extra LED lights)
Replacement aluminium lower bearing dust shield - You will not be able to use any parts from the Bajaj headset for the PX one, they look the same but are different trust me
A reasonable gauge selection of wires to be used to graft in new loom
Switches -
Removal of the headset:
Before you do anything, you must do this to save time later on - Using a can of spray snow, move the front of your scooter ten feet away from a wall, turn on your headlamp and get an assistant to spray a dab of spray snow or other removable marking material at the brightest point of light in the centre there, also use the spray snow to mark exactly where your scooter stand feet are so you can put the scooter back in the same exact position later on. The reason for doing this is to make adjusting the headlight an easy job and getting it in the same position as your Bajaj headlight, when its all done and working, all you have to do then is put the scooter back in the same position noting where the stand feet are and loosen up the aiming bolt under the headlight and adjust until you get the beam in exactly the same position as the old Bajaj beam.
Disconnect your battery and remove it to save the fuse and also reduce the risk of damage by spilling when tipping the scooter.
You will need to disconnect your gear, clutch, front brake cables before anything else, under the clutch and front grab levers, undo the locking nut and then use a flat blade screwdriver to remove the pin pivot, pull the inners out completely of your clutch and front brake. You must remove the solderless nipples and if the front brake cable is so twisted and rotten its not going to pull through it would be expedient to cut it and replace with a brand new inner cable.
Removing the forks:
You would have pulled the cable inners for the brake and speedo out in the above step, you can leave the outers in situ or can remove then before you do anything else, I took mine out for fear of damage when removing the fork but the choice is yours.
The forks come out exactly the same way as any large frame non-T5 Vespa's, you simply with hammer through screw driver, tap the top lock ring round gently until it comes off, take off the tongued washer then tap round the second lock ring which has the bearings underneath it, go at it like a lamb not a lion, you can use mole grips or a bicycle C spanner but all do the job but the idea is to knock the rings off GENTLY as you could fracture them unknowingly and then when you are speeding round a corner the stresses split the ring, suddenly you are in the hedge or under a lorry!
Now I thought it would be hard to take the forks out themselves but I stood on the right hand side of the legshields and gently tipped the bike over on the stand leg, the engine weight helps you here and you need to pull her about 45 degrees and an assistant can without any problems pull the whole forks free. You will need to put a block or something under the scooter to stop the engine weight pulling her over, a milk crate is your best friend for many jobs and is ideal for this.
Readying the forks for installation:
You will need to remove from the Bajaj the ball raiser and also the ball raiser from the PX forks as they are not compatible, you can of course if you have the fifth wheel drift, knock out the PX's lower fixed bearing race but the Bajaj bearings are bigger and a snugger fit.
To remove the ball raisers, once the forks are out, you will need a drift, a lump hammer and patience and no children about because you are going to swear, the aluminium dust and grease shield is going to be toast, however hard you try to be gentle it is very thin alloy and will in the end look like a car crash. Luckily the part is uniform on both scooters and costs a couple pounds for a new one, using firm strokes drift the collar that sits above the shield up along the shaft, you will need to use the shield at first to get the first few mm's before you can move it up further, try and not damage the fork shaft as too heavy digs will need to be dremil polished out or you won't get the other ball raiser in place.
Once removed, inspect the raiser, use a sparing amount of metal polish and give it a clean and make sure you set it aside for the right set of forks (not like me who ended up putting the PX ball raiser back on the PX forks D'oh).
After cleaning the area where its to go down, you can do two different things to get the ball raiser in place:
The oven method makes it a lot easier but the raiser has to be HOT and you will need to handle with oven proof gloves, it will gently tap down with little effort this way.
Alternatively, as I did the second time being frustrated, using a blunt drift, I just tapped it into place with my lump hammer.
IMPORTANT : YOU MUST FIT THE DUST SHIELD IN PLACE BEFORE YOU FIT THE BALL RAISER!!!!!
Once in place the dust shield should be fully horizontal and firm against the ball raiser, not loose or at an angle otherwise you will find yourself with dangerous steering.
It is worth fitting the speedo outer and brake outer now before you fit your mudguard. Check everything is OK, fit your mudguard and you are ready to put the forks into the frame.
Fitting forks and setting up:
Go back to the steering tube and liberally grease the steering race thats in the bike using a high quality grease. Then grease the dust shield also liberally with grease on the forks, get your bearing race and side that down the fork sitting it squarely on the ball raiser and give it a dab of grease too (the excess will squeeze out).
Reversing the way you took them out, tip the bike on its stand to an angle and an assistant can carefully push the fork tube up into the hole being careful not to dislodge the bearing race, wiggle it up through the top then lean the scooter back to its normal position which will push it up into the steering stops, it is important to remember to keep the wheel straight forward so the bearing meets the race squarely and the lock to lock tab fits right.
With your assistant, with the steering pointing dead centre, take the scooter off the stand and sit on it, grease the headset race, fit the bearings, then the bearing lock ring and tighten it until the steering turn feels "notchy" and turn it back a tad till it feels smooth lock to lock. Fit the tongued washer and then the upper locking ring which should be tightened as tight as it can go and then give the bike a good few "bounces" by jumping up and down on the seat to seat it all, put it back on the stand and you should hopefully have no vertical or horizontal play, if you do, off the stand, redo the bearing race and rings and try again, when you are happy that there is no play at all and everything feels good and secure, you have done the hard part.
Fitting the headset:
Wiring in the headset to the Bajaj loom:
Interestingly enough looking back after most of the hard work has been done, the Bajaj and PX wiring looms are fairly compatible, the three wire indicator switch is easy to fit, the main switch needs a little more fiddling, its not something to easily relate to here and with some common sense and the wiring diagram which I will supply in due course you will see how it works.
For the headlight I cut the loom off the bulb holder and fitted crimps to fit to the new one utilising the Bajaj multiplug still in situ.
For the indicator repeater again I cut the bulb holder off from the multiplug and depending on which speedo you use, wired it into the correct directional indicator.
For the speedo illumination I cut the speedo light holder off and wired that directly into the speedo's illumination circuit.
For the "lights on" I nipped a loop of wire from the speedo illumination circuit to the bulb so when the speedo lit up so did the "lights on"
For the Headlamp main beam indicator I utilised from the bulb holder loom the wiring to power this thus saving a lot of time and effort.
The front brake light switch which should be an inline one now will wire directly into the two bullet connectors from the old one.
The Vespa starter switch is also a simple two wire plunger type identical in operation to the Bajaj one so simply wire the two wires onto the old ones will see the starter working.
The indicator switch itself is simple, the blue and green coloured wires are your indicator directional lines, the greyish white wire is the feed, simple job to test before you close the joints to make sure you got the right sides.
Testing and closing up:
In this page I will be taking you through the task of replacing the Bajaj forks with stock PX forks and what you will need and what you will need to do, you will be surprised just how easy it really is and I hope to take the pain and swearing out of the project for you as well by going through it step by step.
I will say here and now it is not a job for the fainthearted, it looks easy BUT you are dealing with the very one thing that can make or break a safe ride.
Tools needed:
Socket and spanner selection
Straight and cross screwdrivers
Mallet and hammer through flat screwdriver or long thin blunt chisel
Wire cutters
Terminal crimp pliers
Rubber mallet (for lifting the headset off if stuck)
WD40/De-greaser
(Optional) Dremil polishing kit
(Optional) Torque wrench
Items needed:
Grease (good quality one as these bearings are out in the open 24/7)
Terminal connectors
Loom tape or loom heatshrink
Good quality insulation tape
Cleaning rags and protecting cloths for new parts
Complete Vespa headset including pinchbolt, switchgear, speedo, speedo cable, front brake switch, starter motor switch, headlight and bulb holder, bulbs, repeater bulbs and gems if using a MK1 headset top (I would not recommend this as you have no need of a second ignition switch, use the better if you can EFL headset top and the larger speedo with the extra LED lights)
Replacement aluminium lower bearing dust shield - You will not be able to use any parts from the Bajaj headset for the PX one, they look the same but are different trust me
A reasonable gauge selection of wires to be used to graft in new loom
Switches -
- For Indicators you need a THREE wire one from either a PK or PX, you can use a six wire and simply trim back one wire from each switch position pair or just simply blank them off by insulating the ends of the three you do not want.
- For lights there are a few options here, there are ones for models with parking lights, there are the more common PX ones for those without parking lights, get the switch if you can that has the screw terminals built into the back of the switch as it makes life easier.
- The Vespa two wire starter plunger switch fitted to later PX's is perfect to replace the Bajaj two wire starter button
- It is very important to get the RIGHT main switch as some use "opener" horn buttons and some use "shutter" horn buttons, the Bajaj is the shutter type where pushing the button creates a connection and very important to get this right.
Removal of the headset:
Before you do anything, you must do this to save time later on - Using a can of spray snow, move the front of your scooter ten feet away from a wall, turn on your headlamp and get an assistant to spray a dab of spray snow or other removable marking material at the brightest point of light in the centre there, also use the spray snow to mark exactly where your scooter stand feet are so you can put the scooter back in the same exact position later on. The reason for doing this is to make adjusting the headlight an easy job and getting it in the same position as your Bajaj headlight, when its all done and working, all you have to do then is put the scooter back in the same position noting where the stand feet are and loosen up the aiming bolt under the headlight and adjust until you get the beam in exactly the same position as the old Bajaj beam.
Disconnect your battery and remove it to save the fuse and also reduce the risk of damage by spilling when tipping the scooter.
You will need to disconnect your gear, clutch, front brake cables before anything else, under the clutch and front grab levers, undo the locking nut and then use a flat blade screwdriver to remove the pin pivot, pull the inners out completely of your clutch and front brake. You must remove the solderless nipples and if the front brake cable is so twisted and rotten its not going to pull through it would be expedient to cut it and replace with a brand new inner cable.
Removing the forks:
You would have pulled the cable inners for the brake and speedo out in the above step, you can leave the outers in situ or can remove then before you do anything else, I took mine out for fear of damage when removing the fork but the choice is yours.
The forks come out exactly the same way as any large frame non-T5 Vespa's, you simply with hammer through screw driver, tap the top lock ring round gently until it comes off, take off the tongued washer then tap round the second lock ring which has the bearings underneath it, go at it like a lamb not a lion, you can use mole grips or a bicycle C spanner but all do the job but the idea is to knock the rings off GENTLY as you could fracture them unknowingly and then when you are speeding round a corner the stresses split the ring, suddenly you are in the hedge or under a lorry!
Now I thought it would be hard to take the forks out themselves but I stood on the right hand side of the legshields and gently tipped the bike over on the stand leg, the engine weight helps you here and you need to pull her about 45 degrees and an assistant can without any problems pull the whole forks free. You will need to put a block or something under the scooter to stop the engine weight pulling her over, a milk crate is your best friend for many jobs and is ideal for this.
Readying the forks for installation:
You will need to remove from the Bajaj the ball raiser and also the ball raiser from the PX forks as they are not compatible, you can of course if you have the fifth wheel drift, knock out the PX's lower fixed bearing race but the Bajaj bearings are bigger and a snugger fit.
To remove the ball raisers, once the forks are out, you will need a drift, a lump hammer and patience and no children about because you are going to swear, the aluminium dust and grease shield is going to be toast, however hard you try to be gentle it is very thin alloy and will in the end look like a car crash. Luckily the part is uniform on both scooters and costs a couple pounds for a new one, using firm strokes drift the collar that sits above the shield up along the shaft, you will need to use the shield at first to get the first few mm's before you can move it up further, try and not damage the fork shaft as too heavy digs will need to be dremil polished out or you won't get the other ball raiser in place.
Once removed, inspect the raiser, use a sparing amount of metal polish and give it a clean and make sure you set it aside for the right set of forks (not like me who ended up putting the PX ball raiser back on the PX forks D'oh).
After cleaning the area where its to go down, you can do two different things to get the ball raiser in place:
- Heat the raiser in the over
- Drift it into place cold
The oven method makes it a lot easier but the raiser has to be HOT and you will need to handle with oven proof gloves, it will gently tap down with little effort this way.
Alternatively, as I did the second time being frustrated, using a blunt drift, I just tapped it into place with my lump hammer.
IMPORTANT : YOU MUST FIT THE DUST SHIELD IN PLACE BEFORE YOU FIT THE BALL RAISER!!!!!
Once in place the dust shield should be fully horizontal and firm against the ball raiser, not loose or at an angle otherwise you will find yourself with dangerous steering.
It is worth fitting the speedo outer and brake outer now before you fit your mudguard. Check everything is OK, fit your mudguard and you are ready to put the forks into the frame.
Fitting forks and setting up:
Go back to the steering tube and liberally grease the steering race thats in the bike using a high quality grease. Then grease the dust shield also liberally with grease on the forks, get your bearing race and side that down the fork sitting it squarely on the ball raiser and give it a dab of grease too (the excess will squeeze out).
Reversing the way you took them out, tip the bike on its stand to an angle and an assistant can carefully push the fork tube up into the hole being careful not to dislodge the bearing race, wiggle it up through the top then lean the scooter back to its normal position which will push it up into the steering stops, it is important to remember to keep the wheel straight forward so the bearing meets the race squarely and the lock to lock tab fits right.
With your assistant, with the steering pointing dead centre, take the scooter off the stand and sit on it, grease the headset race, fit the bearings, then the bearing lock ring and tighten it until the steering turn feels "notchy" and turn it back a tad till it feels smooth lock to lock. Fit the tongued washer and then the upper locking ring which should be tightened as tight as it can go and then give the bike a good few "bounces" by jumping up and down on the seat to seat it all, put it back on the stand and you should hopefully have no vertical or horizontal play, if you do, off the stand, redo the bearing race and rings and try again, when you are happy that there is no play at all and everything feels good and secure, you have done the hard part.
Fitting the headset:
Wiring in the headset to the Bajaj loom:
Interestingly enough looking back after most of the hard work has been done, the Bajaj and PX wiring looms are fairly compatible, the three wire indicator switch is easy to fit, the main switch needs a little more fiddling, its not something to easily relate to here and with some common sense and the wiring diagram which I will supply in due course you will see how it works.
For the headlight I cut the loom off the bulb holder and fitted crimps to fit to the new one utilising the Bajaj multiplug still in situ.
For the indicator repeater again I cut the bulb holder off from the multiplug and depending on which speedo you use, wired it into the correct directional indicator.
For the speedo illumination I cut the speedo light holder off and wired that directly into the speedo's illumination circuit.
For the "lights on" I nipped a loop of wire from the speedo illumination circuit to the bulb so when the speedo lit up so did the "lights on"
For the Headlamp main beam indicator I utilised from the bulb holder loom the wiring to power this thus saving a lot of time and effort.
The front brake light switch which should be an inline one now will wire directly into the two bullet connectors from the old one.
The Vespa starter switch is also a simple two wire plunger type identical in operation to the Bajaj one so simply wire the two wires onto the old ones will see the starter working.
The indicator switch itself is simple, the blue and green coloured wires are your indicator directional lines, the greyish white wire is the feed, simple job to test before you close the joints to make sure you got the right sides.
Testing and closing up: