LAMBRETTA SERIES 2 ENGINE SWAP – PART 2: The rebuild | FEATURE

Linsey sat on her scooter with another ancient local relic in the background…

In part one we dropped the old engine out of Linsey’s Series 2, rebuilt a new 200 engine and fitted an AF Rayspeed Clo5e ratio gearbox.

In part 2 it’s time to change a few cables, refit the engine, get it running and more importantly, make sure the owner is happy before she rides it to Bridlington this weekend.

Degreasing

With the engine out we could give the frame and internals a thorough clean using good old-fashioned Jizer. Once clean, we protected the original paintwork and exposed metal showing through the worn paint using a can of anti-corrosion spray.

The land of no return

Linsey has been riding scooters for the last four years and has only had her full licence (and this Series 2) for two years. Until now, she hasn’t been involved in any garage-based activities (she thought I just kept disappearing for hours on end and the scooters ran forever with no maintenance).

She really enjoyed getting stuck in and learning where things go, what’s what and how stuff works on her own scooter. Hands-on experience is the best way to learn, although after two full days in the garage and a few typical scooter-based problems along the way, her enthusiasm began to wane. You can’t always predict the things that are likely to go wrong when messing about with scooters.

Powder coating

Whilst the scooter was in bits it also gave me the chance to send the rear mudguard, centre stand and cowlings off to be powder coated, as well as a new rear hub and two new sets of wheel rims from VE.

I also had a new set of cables to put in and placed an order for a few items like new panel rubbers, a cable sheath, rear brake shoes, nuts, bolts and sundries with Scootopia. Sadly on the day my order was being posted out they suffered a fire at the unit and the parts were delayed for about 10 days (fair play to them though everything came out as promised and as quickly as possible).

“Let’s get some lube and the rubber gloves out this weekend love…”

Easy to work on

After years of needing the hands of a small child to help when fitting Vespa cables, a Lambretta seems so much easier to work on. With the front horncast/mudguard removed (a five-minute job) you can see exactly where the cables go and replace them by simply feeding them through. Loads less bother than on a Vespa.

The spray booth

I also replaced the broken brake light switch and bought an almost new V4 BGM exhaust to replace the well-used V3 one already fitted. The exhaust was hung in my favourite exhaust spraying tree in the garden to get a few coats of black high-temp paint ready for when we needed it. A few other odds and ends were also replaced whilst I was waiting for parts.

The frame and any exposed metal were coated with this…

Grind it

My local powder coater rushed my job through (the off-white he uses is a great match for the original colour) and I had the fresh bits back in less than a week. I always find Lambretta rims when they’ve been coated are too tight to fit onto the shoulders of the hub. Try to force them on and it just cracks the powder, so I used the Dremel just to get it back to bare metal on the very edge of the rims, then coated them with anti-corrosion spray. Once fitted, you can’t see the missing paint and the spray just helps to keep the rust at bay.

Incompatibility

I’d sent the cowlings off the old engine to be coated, when they came back and I tried to fit them I realised that the new engine had a deeper finned flywheel fitted (schoolboy error). Also, the head cowling wouldn’t fit because the new barrel had been skimmed slightly so I ended up fitting the chrome cowlings it came with before fitting the engine.

Saturday – engine fitting

With all the odds and ends replaced, it was time to fit the freshly powder-coated stand. This gave us a little problem; the stand had been welded/bodged sometime in the distant past and the wonky bottom leg meant the rubber wouldn’t fit well enough to get a stand pin through. After an hour of messing about, I used the ever-useful Dremel to grind some of the rough weld away. It didn’t take long before the weld opened up and the bottom of the leg dropped off! Not really the plan I had in mind but not to worry (I bought a new stand the following day from Wicksteed).

Two hands are better than one

Having a garage assistant certainly made it much easier to line things up to get the engine bolt through. As with all bolts and fittings, I copper-greased the engine bolt before sliding it through to make removal easier the next time the engine comes out.

Almost finished

Once the engine bolt was in place and the BGM rear shock refitted, it was time to fit the rear hub and wheel. Then, fill the gearbox with fresh oil. All the new cables needed setting up, then the electrics were plugged back in, the exhaust fitted and a final checkover was done to make sure nothing was loose or likely to drop off.

Minor problems

We’d both pretty much had enough by this stage and a few things had gone wrong:

• I was struggling to get the clutch to engage when adjusting the cable
• The gears were sloppier than they should be and I didn’t have a clue if all five would even select
• The new choke cable inner was way too long
• The throttle cable was too short for the 25mm carb. I ended up swapping those two back to the old cables, luckily I’d not binned them
• We also had hassle trying to fit the chrome cable clamp for the dummy oilers (I reckon there’s a knack to it)
• I had to undo the tank and refit the rubbers because the fuel tap was touching the engine mount
• The wiring loom had gone beneath the engine mount as well when we put the engine in, so I had to partially remove the engine bolt to lift the wiring to where it should be

Other than that, it was plain sailing, and if it failed to start as well, we’d probably have thrown our toys out of the pram good and proper.

First start up

Fresh fuel and oil in, choke on, fuel on. Ten or so kicks and… nothing. Spray a bit of carb cleaner down the carb, a couple more kicks and it attempted to start. The mood rose slightly. Another couple of kicks and the scooter burst into life… for about 20 seconds then died but that was good enough for now. It lives.

The scooter still needed a few bits finishing off and adjustments made before it could be ridden (I’d not connected the front or rear brake at this stage and didn’t have a working clutch). Even so, it was a relief that it started, but a worry that the clutch may have to come out. Even so, it runs and the hard work was done for the time being.

Monday

I was at the Wicksteed parts fair on Sunday, so it had to wait until Monday when our club mechanic, Alister, popped around to set the timing up (there’s never a Buzzwangle around when you need one). The scooter still took a bit of starting from cold, but once it was running, we decided to swap the flywheel back to the shorter-finned one from the old engine. This allowed me to use the freshly powder-coated cowling. Alister strobed the engine up, set the mixture and let the engine run for a bit, then had a play with the clutch and gears. Thankfully, once a bit of oil had gone around the engine, the clutch was working fine, and we could select all the gears with the back wheel propped off the floor. Things were looking up.

Final fettling

After Alister left, I finished sorting the brakes out and fitted the exhaust properly now that I knew the sidecasing wasn’t going to have to come off again. I also tidied the wiring and cables up before refitting the front horncast/mudguard. Finally, I was able to take it out for the first test ride. The gears were still very hard to select, and the clutch needed adjustment, so a bit more fettling was required.

With a few adjustments and a few test rides, it was feeling much more like it should and I took it out for a 15-mile ride. Other than the clutch dragging (I had to adjust it a bit at the roadside), the scooter was feeling quite smooth and nice to ride. The new engine sounded good through the new exhaust, it picked up well (MB-tuned stage 4 top end doing its job), and it was easy enough to go through the AF 5-speed gearbox, so I was feeling much happier.

Deflated

One more minor issue though, later on that day the rear tyre was flat – I’d obviously trapped the inner tube when building the wheel. Despite me being careful and partially inflating it to stop it from being trapped between the two rim halves. Wheel off, tube swapped and wheel back on. Better to happen now than on the road to Brid I suppose.

Linsey’s first test ride

By this time I’d already done about 30 miles on the scooter, but Linsey is the owner/rider, so I was hoping she’d like it. On her first small ride around last Friday, she was struggling to get the gears and the clutch was harder to pull in than the old one. Her second test ride was a bit longer but she was still struggling a bit to get to grips with it.

We called in at Simply Retro whilst we were out and Rob adjusted the gears again for her. She said it felt better on the way home but her left thumb area was really hurting (she dislocated it a couple of years ago) and she was worried she couldn’t do the 100-mile ride to Bridlington this weekend.

Sunday

I expected to be whipping the clutch out and putting the softer one out of her old engine in on Sunday (not that I really had the time or inclination to swap a perfectly good clutch for one that was a little lighter). Luckily for me, Linsey had got her head in the game and decided we’d do a 40-mile ride to see if her aching hand could cope. Within a mile or so she was visibly enjoying the ride, she was sounding happy over the intercom as well (a blessing in itself) and during the course of the ride her whole demeanour changed.

On the way home, she was telling me how much she loved the new engine and how slow running it in felt. She’d got to grips with the AF Clo5e ratio gearbox as well and seemed to be liking the extra gear. Even though it’s too early to see how much benefit she’ll get from it until it’s run in a bit and she can open it up properly.

Bridlington or bust

Other than a few little adjustments, the scooter is ready for Bridlington. I’m going to fit a Scootronics CDI this week to see if that helps it to start better from cold (it’s not starting as well as it should), although Anthony Tambs says it’s more likely to be the pickup height or air gap causing it. I’ll try a diagnostic CDI, though, first. My Series 1 kicks up for the first time since fitting one a couple of months ago. Other than that, it’s good to go.

If you see Linsey waiting for the recovery service this weekend don’t take the mickey out of her, there’s every chance she’ll be proper mad and I’ll be killed later on…

Words and photos: Iggy

Thanks to: Alister, Simply Retro, BGM, Scootopia and AF Rayspeed for parts and help