PR Motorcycles

07/12/2025

Classic Yamaha SR125: When “No Spark” is just the beginning... 🔧📉

​We had this lovely little Yamaha SR125 in the garage recently. It broke down on a customer and came to us with a suspected “no spark” issue.
​While the ignition coil tested bad and gave poor readings, my ear caught something else—the engine just didn’t sound right turning over. It sounded “loose,” a classic sign of low compression. We decided to dig deeper to get the full picture.

​The Diagnosis Process
To confirm the internal health of this SR125, we ran two critical tests:
​Compression Test: We removed the spark plug, screwed in our Sealey compression gauge, and held the throttle wide open (WOT) to let the engine breathe. We cranked the engine until the needle peaked. A healthy SR125 should be pushing 120+ PSI. As you can see in the photos, this one struggled to hit 40 PSI.
​Leak Down Test: To find where the pressure was going, we set the piston to Top Dead Center (TDC) on the compression stroke (valves closed). We hooked up the dual-gauge leak down tester and pressurized the cylinder. The results showed massive leakage, and we could hear the air escaping—confirming significant internal wear.

​The Verdict:
The numbers don’t lie. Between the electrical faults and the internal engine wear, the bike needs a serious rebuild.
​However, with the customer’s “Big Bike” test looming on the horizon, we’ve decided to postpone the repairs for now. Sometimes it’s better to save the budget for the next machine!

​Good luck on the test, mate! 🏍️💨

🏍️🛠️🔩

09/11/2025

23/10/2025

Project Spotlight: 1990s Kawasaki ZX-9R Recommission

This recent project was a perfect example of what we love to do: recommission an old, unloved machine. Found in a garden in Essex, this ZX-9R was non-running and required a complete mechanical and electrical assessment to ensure viability.

Key Mechanical Work Completed:
* Fuel System: Carburetors removed, fully stripped, ultrasonically cleaned, and rebuilt using a Tourmax overhaul kit, followed by a precision carb balance. The engine now runs smoothly, with the gearbox fortunately showing no issues despite years of neglect.
* Braking & Suspension: Full front-to-back suspension and braking system overhaul, including caliper rebuilds, new pads/discs, fork service and rebuild, and rear shock linkage service.
* Drivetrain: New headrace bearings, chain, and sprockets.
* Wheels & Tyres: Wheels refurbished and fitted with new rubber, along with new wheel bearings.

Addressing Hidden Issues: During the process, we corrected several dangerous bodges, including damaged screws, incorrect wiring, poor cable routing, and the use of jubilee clamps on the ram-air pipes.
Following a comprehensive final service and road test, the bike was returned to a delighted owner, fully functional and MOT-ready.

🏍️🛠️🔩

11/10/2025

Would appreciate if you’ve got the time to drop me a review on Google 🙏🏼

🏍️🛠️🔩

28/09/2025

It's been a little quiet on the social media front lately, but only because I've been slammed in the workshop! 🔥 The jobs have been coming thick and fast, and I'm thrilled to see so many new and returning customers leaving happy.
​I've been non-stop on the tools for a great mix of work, including:

​On Two Wheels:

​A full recommissioning job on a classic CBR1000F

​MOT repairs on a trusty Piaggio PX scooter

​Chain and sprocket replacements

​Solving a persistent timing cover seal leak on a BMW GS

​Complete clutch replacement on a modern Triumph

​Brake caliper overhauls for a couple of Honda and Kawasaki machines

​The fun challenge of rewiring an interestingly modified bitsa bobber

​Steady stream of carburettor ultrasonic cleaning and rebuilds

​A little closer to home (Four Wheels):

​Repairing a Range Rover DPF issue and central locking fault.

​A fix for the trusty old Transit and its nagging AdBlue fault.

🏍️🛠️🔩

28/09/2025

Website Now Live 🛜

www.prmotorcycles.com

🏍️🛠️🔩

04/08/2025

Squeezed in a last-minute job this weekend, fitting a Healtech iQSE quickshifter to a sweet CBR 600. It's always a pleasure working with these kits—the app setup is super simple, and the whole install is pretty much plug-and-play. Just gotta be mindful of the wiring and cable routing, and you're golden. Another happy customer and another bike ready to rip!

🏍️🛠️🔩

13/07/2025

Saved the Day for a Piaggio PX 125!

Just wanted to share a recent win! A super nice customer brought in their Piaggio PX 125, which was due for its MOT soon and had decided to throw a major electrical wobbler. I’m talking no electric start, basically no lights (except for one lonely indicator), and a dead brake light. Not exactly ideal for hitting the road, right?

I dove straight into it, figuring out what was causing the headaches. First up, the regulator/rectifier. I have a standard way of checking these – basically, I’m making sure it’s taking the power from the engine and sending it to the battery at the right, steady voltage. If it’s all over the place, it’s usually a goner.

Then I moved on to the CDI (Capacitor Discharge Ignition) unit. This little box is crucial for getting a spark. I’m checking its inputs from the stator (which was fine on this one!) and verifying that it’s correctly sending the signal to the ignition coil to create that spark. A common way to check involves looking for specific resistance values.

Long story short, both the regulator/rectifier AND the CDI unit were found to be faulty! Good news, though, the ignition coil (and the stator) were totally fine.

Now, things got a little spicy when the new regulator/rectifier I put in also turned out to be faulty – talk about bad luck! But I quickly got another one in, and boom, everything was back to normal. While I had the scooter, I also spotted and fixed an oil leak, so it’s running super clean now.

As part of my pre-MOT check, I also found a couple of other potential issues that the customer’s aware of. They’ll be bringing the bike back soon for me to sort those out too, keeping this PX 120 on the road for ages!

It’s always awesome getting a customer’s ride back in tip-top shape, especially when it’s a bit of a puzzle.

🏍️🛠️🔩