Is R15-S’ Engine Different From R15V2’s? We Clarify

R15 S vs R15 v2 – Is there something Yamaha is hiding?

Few months back we did an article listing all the spec differences between the R15 v2 and the unibody R15 S. We updated it recently informing our readers how has Yamaha repositioned the R15S and increased V2’s prices. You can read the article here.

One of our reader shared a very interesting article from another website in the comments section which tried to portray that R15S may not carry the original full-blown technically advanced motor of the V2. You can read that article here.

Broadly, the pointers which he raised, after riding both the motorcycles, were..

• R15S may NOT have a DIASIL cylinder.
• It may NOT be a 4-valve motor.
• The engine is not responsive enough (as much as the R15 v2).
• He suspected that Yamaha may have slapped the head of fuel injected FZ to save costs.

His apprehensions were well supported by the fact that Yamaha missed out on some crucial details on the R15S’ webpage like

• they haven’t revealed the bore x stroke numbers
• is it a DIASIL cylinder or even if it is a 4-Valve motor

While all or most of these details are proudly mentioned on R15 v2 and other motorcycle webpages. But the biggest pointer that got me confused was – Yamaha NEVER officially said that these are absolutely the same engines. And since the motorcycle is perceived to be just a variant of the R15 v2, no mainstream media bothered to test it out!

So, there were two aspects to it – try the new R15-S myself and have a word with Yamaha’s spokespersons to have an official word from them.

Two days later, I borrowed one of my friend’s new R15S and took it out for a spin. Frankly, it was not a very long ride but I could NOT really find a massive difference, substantial enough to doubt it as the FZ-derivative (motor).

R15 s VS R15 v2 – Engine Differences?

Next I connected with Yamaha’s Communication head of India and posted these questions…

1. Does R15-S’ engine have 4-valves?
2. Is it the same DIASIL cylinder of the R15 v2?
3. Is there any difference in the engine block of R15 v2 and R15 S?
4. Can I please have the exact bore and stroke numbers for R15S?

Also Read: Yamaha Has NO Plans to Offer ABS on Fazer 25 (or FZ 25) Anytime Soon

The corporate communication guy polite guy asked me to wait for some time as he would pass on these queries to the concerned (I believe the technical) teams. Few days back I received the responses to all of these and here they are….