61x and 62t

[ryallshire]

dont know weither there is a thread for this can't find it,
Where does the extra 10 hp on stock 61x and 62t 61x come from, is it just the twin carb??
If so what size carb can you run on 61x to get more power from it?

 

[Quinc]

The cases are also different/more efficient.

 

[ryallshire]

Can the 61 x cases be made as efficient ??

 

[Quinc]

You can port your cases.

Get the most bang by: adding a decent exhaust pipe, high compression head, the correct pitch impeller, and having your cylinders ported. The 61x is a very capable engine. Unless you are racing and looking for that extra 1-2mph. You can also get a WetJet Kraze 46mm intake manifold with built in reed stuffers. Pricey and hard to find though.

 

[ryallshire]

I have pipe and head just wondering tech aspect where the 10 hp comes from. I run both engines and don't find the 61 x lagging

 

[BruceSki]

61x makes a bit more bottom end than 62t. There is less volume and more velocity for the air. Little bit more snap but falls flat faster than he 62t once you hit the higher rpms. The intake tract in the cases and the reeds are the big difference.

 

[kevbo]

I have pipe and head just wondering tech aspect where the 10 hp comes from. I run both engines and don't find the 61 x lagging

It comes from Yamahas marketing department. Peak power is limited by the small 61X exhaust port. You can find magazine reviews of 95 and 96 Blasters, they have identical pumps and go the same speed despite the 96 claiming 10 more HP. 62T cases get better with mods but dont do much for stock ported cylinders, especially with the stock exhaust.

 

[paczowski123]

I have pipe and head just wondering tech aspect where the 10 hp comes from. I run both engines and don't find the 61 x lagging

I agree with the X not lagging, but let's keep this on the hush so that the parts stay so cheap!!

But on a more serious note, I have never considered the X to be lagging, at least for what I'm looking for. I want instant power, I care nothing about top end speed, but I also don't race. For me, the X setup is reliable, easy to tune, and has plenty of power for where I want it in the low-mid range. My bored/ported setup with a head 46mm carb lightened flywheel and enhancer is IMO a arm ripper. Now, it's no true BB, but for a 735, a some of my friends ask me how I hang on. For me, I will stay with my X setup until I go to a true BB engine and am forced to go dual carb. My opinion becomes more concrete when I see riders stuck fooling with dual carbs on the shore: 4 jets (which in sometimes can all be different), plus 4 mixture screws (which again can differ in adjustments between front and back carbs), and continue riding. To me, like others have mentioned, the slight mid-top end difference is not worth the hassle in jetting and carb adjustments. Ok...off my soap box.