I have an underbone motorbike that has been inactive and decided to revive it as another mode of transport for me. The bike is old and sort of gotten it from a neighbour after his beloved dad passed away. It was used to carry the kids to school, college and work by the late owner. Blame me for being sentimental; i see it as a mean to continue the legacy as well.
I have previously sent (and spent) time to fix the piston seal and changed the clutch spring, fixed the brakes, speedometer cable and fixed a few bent items about a year ago.
Underbone motorbike will often receive a change in the look once the tire are changed - and it can be a significant change - from an Uncle Commuting Bike to a Racing Machine (or look like one). I had a few choices but because my other bike was having a Pirelli Demon shod and I know how it ride and felt, I decided to ask if they have Pirelli stored at this humble looking local motorbike shop... and surprised that they did at a price I can't resist! They have the Pirelli Angel CiTy (written as Angel CT) at 80/90-17 44S TL sizing, which fits the underbone, and a good replacement of the original 70/90-17 tires.
This Pirelli is made in Malaysia and there is nothing shy about it as we do produce rubber as one of our commodity resources. First visual impression of the thread was impressive. Having a semi-slick rubber was pretty exciting for an underbone - i was right about the look like one fast bike.
The Angel City is directional tire where there is a specific direction should it be installed at the back or the front. I made the decision to have both the tire rolling in same direction, instead having the front to be the other way around. May be detrimental on speed and control if the bike is being pushed beyond 120km/h - and I do not see myself pushing it past 90km/h on this smaller bike; but will change the direction if the road test proved it to be detrimental to both handling and safety.
The underbone comes with sports allow rim and it is a bit old due to dirt and accumulated road grime that embeded itself into the rim, so it's a bit unsightly
Nothing a bit of sticker (reflective at that!) can't fix... and it's yellow, so that's good!
I have previously sent (and spent) time to fix the piston seal and changed the clutch spring, fixed the brakes, speedometer cable and fixed a few bent items about a year ago.
Due to the leaking piston seal, the bike dies off when idling and it is no fun keeping the throttle on. This repair/revivial involved change to the drivetrain which is the front and rear sprocket and the chain. It is best to change it as a set, and this is the highest wear and tear on a motorbike.
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| Front sprocket old vs new. Both 14 teeth |
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| Rear sprocket - new is 36T, old was 40T. Not immediately noticeable, but the teeth on old sprocket has thinned out and sharper. Smaller new sprocket allows higher speed at same RPM (better final ratio) |
While the sprockets were removed and the wheels were off, I asked for the wheel bearings to be checked and replaced as needed. Good move as the front bearing has seen better days.
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| These make great Fidget Spinner core - which I did |
Heck, I even gotten the front fork removed and serviced, with the old seal replaced and new hydraulic oil - thinking back, replacing a new fork will just cost RM40 more (vs RM50 to service it).
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| All in the name of safety |
As the underbone is under utilised and I want to sort of flush the engine oil it, best way is to run a liter of new engine oil for a few hundred kilometers or a tankful or two of fuel and then change the engine oil again.
The Changing Of Tires
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| Shell Advance AX5, A Premium Mineral oil at 15-40 weightage |
The Changing Of Tires
Well, of course, after all the repair done above, it is only logical that I consider to change the tires too. The old tire still looked very useable. 80% thread on the rear Dunlop TT100 70/90-17 tires, the front though, need replacing having left about 40% thread.
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| The front Dunlop TT100 70/90-17 tires. Unidirectional. RM75 to replace new. |
Upon removal of the front tires, we noticed that it had glue and likely residues from previous puncture sealants still in there! Which sort of explained the vibration at speed due to imbalanced inertia and the damaged front bearings!
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| The gunks |
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| 80mm widest, 90% Aspect ratio (72mm height), 17 inch rim, 44 speed rating (180km/h max), S load (not sure how many KG loading) and TL (tubeless) |
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| Very nice! |
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| Old vs New |
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| Wow! See what i said about changing the whole outlook of the bike? |
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| The front tire direction in reverse, after 60km |
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| hmmm... |
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| Now, that's better! |
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| And nothing some tire polish can't fix to the look! |
Road Test
As the new tire may be a bit slippery, I was advised not to ride it to aggresively until the tires after a few kilometers (like really?). But he is the mechanic, and he seems competent, and has "race" experience (scars to show on his arms/elbow), i took his advise. Despite the "new slippery" feel, the tire gave me a very high assurance of grip and speed.
I believe that the 'fast" feel is because of the serviced bike, and that the mechanic tuned the air-fuel mixture (again, his "race" experience helped), the bike felt lively. I now know the old mechanic did tune the bike to run leaner for fuel savings/consumption purpose vs this mechanic that tuned it to the near perfect ratio. The new chain and sprocket set may had added slightly more speed with lower drive ratio (higher 40:14 vs lower 37:14). If you make the drive ratio to be higher, you gain higher accelerations.I may just write one article to explain this separately...
Great Dry Handling
So, back to the Pirelli Angel handling - it's good and the slightly higher ride due to the aspect ratio (of 80/90 at 72mm vs the older 70/90 at 63mm), it did provide a plusher ride and gave the bike a slightly larger diameter, which also meant the speedometer will slightly under report the actual speed, not a lot, just slightly as the circumference of the wheel increased by approximately 5cm per rotation. (180.89cm vs 175.24cm - do you remember your maths? ;-)). After about 60km of riding on the road in KL, on straights and gentle corners, the tire gave me higher handling confidence when compared to the older tire handling, significantly. Riding over small uneven (read: small holes), has no issues except that the suspension did struggle to cope (upgrade next?).
Great Wet Handling too!
We live in Malaysia and we have rain that happens suddenly even during dry hot season. In Malaysia, when it rains, it pours - and that was exactly what happened after day 3 of the tire change. The Pirelli lives up to it's name on the wet as well. While this is NOT their top end motorbike tires, the rubber compound provides great grip in the wet over heavy rain and I was riding with a lot of confidence even through corners and roundabout in the wet. I would say this rubber compound provide good grips and assurance both wet and dry!
Long Term Feedback
I will likely be using this same tire over the next few years due to the shorter commute I may have to work and back. Will provide more update mid-wear and tear, or within the next 6-months with visual of how it has worn out over time. Meanwhile, this is the official page for Angel CiTy from Pirelli
I believe that the 'fast" feel is because of the serviced bike, and that the mechanic tuned the air-fuel mixture (again, his "race" experience helped), the bike felt lively. I now know the old mechanic did tune the bike to run leaner for fuel savings/consumption purpose vs this mechanic that tuned it to the near perfect ratio. The new chain and sprocket set may had added slightly more speed with lower drive ratio (higher 40:14 vs lower 37:14). If you make the drive ratio to be higher, you gain higher accelerations.I may just write one article to explain this separately...
Great Dry Handling
So, back to the Pirelli Angel handling - it's good and the slightly higher ride due to the aspect ratio (of 80/90 at 72mm vs the older 70/90 at 63mm), it did provide a plusher ride and gave the bike a slightly larger diameter, which also meant the speedometer will slightly under report the actual speed, not a lot, just slightly as the circumference of the wheel increased by approximately 5cm per rotation. (180.89cm vs 175.24cm - do you remember your maths? ;-)). After about 60km of riding on the road in KL, on straights and gentle corners, the tire gave me higher handling confidence when compared to the older tire handling, significantly. Riding over small uneven (read: small holes), has no issues except that the suspension did struggle to cope (upgrade next?).
Great Wet Handling too!
We live in Malaysia and we have rain that happens suddenly even during dry hot season. In Malaysia, when it rains, it pours - and that was exactly what happened after day 3 of the tire change. The Pirelli lives up to it's name on the wet as well. While this is NOT their top end motorbike tires, the rubber compound provides great grip in the wet over heavy rain and I was riding with a lot of confidence even through corners and roundabout in the wet. I would say this rubber compound provide good grips and assurance both wet and dry!
Long Term Feedback
I will likely be using this same tire over the next few years due to the shorter commute I may have to work and back. Will provide more update mid-wear and tear, or within the next 6-months with visual of how it has worn out over time. Meanwhile, this is the official page for Angel CiTy from Pirelli
- The new Angel™ CiTy is directly derived from the well-known and test winner Angel™ GT. Technology and tread pattern design have been reviewed and adapted to smaller displacement bikes, with a X-Ply construction and dedicated materials
- The new tyre addresses the needs of sporty bikes up to 250cc, ‘underbones’ and other commuting bike
- The robust tyre construction ensures high puncture resistance and performance consistency throughout the entire tyre life
- The benefits of Angel™ CiTy are clearly perceived in any riding condition, especially on uneven road
- The tread pattern guarantees optimal wear and improves water evacuation
- Angel CiTy features a new compound mainly based on carbon black with a calibrated percentage of silica; it is able to deliver excellent grip on both dry and wet, tear resistance and mileage
