Yuminashi variator and belt

[YUMINASHI]

To those that have good luck with yuminashi good for you. There are many people including on the grom forum that have had issues with yuminashi. Including some bore and piston sets that did not match and caused engine failures.

I requested information on a 175 cc yuminashi big bore kit from PCX racing in France. Keep in mind that PCX racing sells the 164 cc bore kit. I was told that PCX racing will not sell the 175 kit because of poor quality. What does that tell you when their distributors will not sell some of their parts...

Please notice that Yuminashi don't have a 175cc kit at this moment, so it's hard to sell something if it isn't available.

Our new pistons for the 175cc will be available in something like 2 weeks.
Until then we will never have sold 1 kit 175cc for PCX.

Concerning the issue with the 5 pistons at the start from the 150cc cylinderkits for MSX/GROM125, all 5 pistons have been replaced in warranty and no issue have been reported so far.
Even better, Travis Butler who is one of the customers who ordered such a kit and showed all the details on internet have installed later on our 160 Ultimate Kit for MSX, and his experiences about this kit you can read over here http://www.hondagrom.net/forums/13-grom ... sults.html.

If a part isn't functioning correct, you will be replaced, and herewith we are the only company in the world with high performance parts for PCX, MSX or Monkey bikes who does this.

[mikelx5]

two were yuminashi and one was stock

[Mgalutia88]

Reggie, my mistake. I was told by a distributor that lists your 175cc kit that it was out of stock and he was manufacturing his own. Another manufacturer told me that he was not selling your 175cc kit because of quality issues. All I was aware of was that fact that your kit was advertised and unavailable. I wish I had known that it wasn't even being distributed yet!

[Mgalutia88]

Can you explain why your distributors say it is not of good quality if it's not available yet?
http://www.yuminashi.com/-pcx150-esp-17 ... ht-bore-k/

[YUMINASHI]

Can you explain why your distributors say it is not of good quality if it's not available yet?
http://www.yuminashi.com/-pcx150-esp-17 ... ht-bore-k/

I can't explain that, I only know that we never ever have sold 1 set so far, even not 1 set to our dealers to test one.
A product must be 100% reliable before we can launch it on the market, and if it takes an other year to do so, then so be it...

[YUMINASHI]

Agreed. I think that is what our forum members here are looking at. Many of us ride at US freeway speeds which means a minimum of 113 kph. Should we be doing this on larger bikes? Probably, however that is where you and other manufacturers come in. We are looking for ways to make touring at those speeds normal. Personally I run 70 mph on a daily basis at around 8500 rpm. I'm looking into ways to lower that rpm for longevity sake but at the moment I'm happy with where I am.

In short we need proven parts and parts we can rely on, no parts (like the pcx 150 esp small valve head that you say you moved away from) that come and go on a whim. We honestly don't want to hear about parts until they are ready to hit the market and have the kinks worked out. I'm sure you can understand this.

Well, we fully understand this and our entire company mission is based on this as you can read over here: http://www.yuminashi.com/company-mission/

I think announcing that we never will make a mistake wouldn't be realistic, we all know that even the biggest companies like Honda, Toyota, General Motors, etc have recalls where they ask customer to return the car or motorcycle to the dealer to improve something.
Important to know for the customer is that the particular brand is worth the trust where they do anything possible to avoid issues, and if somethings unexpected would happen that the customer can be sure that the problem will be solved, and not at the expenses of the customer.

We are aware that product tests before release are very important, and that's why we do so many tests with sometimes a delay from 1 year, like we see not only with the 175cc kit for PCX, but also with the 210cc kit for MSX/GROM at this moment.
Main thing is that the customer receives a high quality product.

[Mgalutia88]

I guess what I'm saying is (no offense) we don't want to be on this adventure of further modifications with you. We would prefer to look at you as an authority in being able to tell us which parts to use for our goals. I hope you can understand this.

An example, recently I spoke to you about your high compression head for the PCX 150. You quoted me a price for the head only and suggested that I use that before I installed a cam telling me that the gains of the cam by itself with your variator would not be very good. Previously you told me that the cam along with the variator would make a good improvement and make me happy. It does not make a difference to me at this point but the majority of your customers will want to install one or two parts and know what to expect. They won't be interested in a full race build.

[YUMINASHI]

I guess what I'm saying is (no offense) we don't want to be on this adventure of further modifications with you. We would prefer to look at you as an authority in being able to tell us which parts to use for our goals. I hope you can understand this.

An example, recently I spoke to you about your high compression head for the PCX 150. You quoted me a price for the head only and suggested that I use that before I installed a cam telling me that the gains of the cam by itself with your variator would not be very good. Previously you told me that the cam along with the variator would make a good improvement and make me happy. It does not make a difference to me at this point but the majority of your customers will want to install one or two parts and know what to expect. They won't be interested in a full race build.

Don't forget that anything I am saying is based on the results we had achieved so far.

I don't remember this particular conversation I must say, but I know that a smaller head with smaller valves and ports makes more power and the video on youtube proves it.
Previously we didn't had the smaller head, so that's why I could inform you at that time that the cam in combination with the variator would make a good improvement.

Give me a month and I will know things again that I don't know today, but that's how it go's if you are looking to improve things Mike.

At this moment the best thing you can do is installing a short gear set, with the camshaft and the speed booster variator on a V1 or V2 PCX150....

[nribeiro]

What I know about big bores from Yuminashi at least here in Portugal is that the PCX where it was installed suffered from over heating. If it's true or not...
That's why I'm not interested to upgrade mine right now. Probably I'll upgrade the camshaft and valve springs from Yuminashi with stock 150cc since mine is a 125cc.
If this is possible probably I'll do like this.

I don't know if only the cam and valve springs do anything... My PCX in the moment with Dr. Pulley sliders and front wind can do 100+ uphill so it's good since with JCosta variator it will do less... The problem is the top speed is affected but in general it's better now.

[Pcxdemon]

Well, from my experience with yuminashi big bore kit I can happily report that if installed right it's reliable and powerful. I've finally bought mini camera like gopro so I'll record some nice footage of it going.

[Mgalutia88]

Here are the pictures of my yuminashi variator with the finish popping off after 2000 miles. I enjoyed it but I enjoy my daytona with sliders far more.

[Mgalutia88]

This happened after two belts came apart because of a bent drive gasket. I replaced the gasket and locator pins and no more issues thought I get the same top end out of a Daytona variator.