Tuning the R50x

[mmcmaster]

I've added 70cc kit and a MRP performance pipe to my R50x and wanted to post a brief review.

I added the Malossi cast-iron 70cc cylinder kit (part number 31.8723, 10mm pin).  Also added is the MRP R50x racing exhaust (part number N-MP-02059).  For reasons explained below, I simply drilled out the main jet to up-jet it--so I can't provide you with an exact size for the jet.  But know that up-jetting is necessary.

Completely stock, with the restrictor, I was topping out at 38 mph (according to the speedo, which we all know is inaccurate).  After these modifications, I'm topping out at 56 mph.  In addition, the torque is substantially better; improving acceleration and hill climbing.

A couple notes about the pipe:  this pipe is loud.  You have been warned.  Also, the pipe has a glossy coating on it.  I've put on approximately 300 miles since installing it and I've noticed that close to the engine's exhaust port, the coating is starting to peel off, as well as become discolored.  I suspect this is a result of the heat, which is inevitable for an exhaust pipe.  I would have though MRP would anticipate this.

These mods turn the R50x into a whole new animal and I would highly recommend them.  I got my parts through Oilyhands and I would highly recommend working with him.  He was helpful, knowledgeable and responsive.  MRP's first shipment didn't contain the jets that I ordered.  Oilyhands worked with them to resend the jets, which they did.  But they then sent the wrong jets, which is the reason I ended up just drilling out the stock jet.  Two separate scoot shops in my area have confirmed that just about every order they make from MRP has some kind of error in it, so I'm confident the error was not Oilyhand's. (MRP seems like an overall good company, but has some problem with shipping).  Regardless, ordering through Oilyhands was a positive experience.

Since ordering from him, he has started a website.  Although I did not use the website, working with him was such a positive experience, I will nonetheless post a link to the site: http://whidbeyislandmoped.com/cart/

Now that the weather is warming up, I intend on tuning my R50x some more and I'll let you guys know how it goes.  On a separate note, since adding the cylinder kit, the in-dash clock does keep very good time and the turn signal timing is a little off.  I haven't really invested much time in investigating it, but wondered if you guys had any thoughts?

[harry]

Good to hear your mod came out well ..and thanks for the good words
fyi: all the pipes i see have that clear coating on them 
i was wondering about that too when i did my first mod and asked the mfg.
seems its there to keep them from rusting all over the thin sheet metal expansion chamber.
do you still have the  stock cdi in there? perhaps a un limited CDI would help
get more top end. 

 oilyhans

[Burnsy0330]

Hey mmcmaster,

I have a 2007 R50X. I was wondering if you could help me. I am wondering how to get the restrictor off. I already have the brass ring off but it only goes like 42ish which is actually like 37. I heard about cutting the brown CDI wire , but i have heard that doesnt work for the R50X. I am probably gonna buy some sliding weights which will help, but my buddies keywest can go 8 or so mph's faster than mine and his is just derestricted. So i figured there is something I could do with out spending alot of money to get it to go faster. I was wondering if you had any info to help me out. Thanks...

[harry]

Perhaps the difference in top speed is due the weight of the scooters,
seems there is about a 30lb difference.

KW--Dry Weight      178.5 pounds
R50X--Dry Weight      209 lbs

Burnsy check it out:
http://tgbforum.com/forum/index.php?topic=40.msg133#msg133

 oilyhans

[rjbosco]

Oilyhans:

I've been debating which way to go to upgrade my R50X for a while now.  I've had my dealer search all over the globe for exhaust upgrades and the only one that seems to fit the R50X (because of its rear disk brake design) is the MRP pipe.  However, I've heard from several sources about how noisy the pipe is and how tough MRP is to work with (my dealer in particular is very soured on MRP).  As a result, I'm now looking at buying a 70cc cylinder upgrade instead of changing the pipe (I can't afford both the cylinder and pipe upgrades).  Can the 70cc cylinder work with the stock exhaust and what kind of improvement in top end speed and torque can I expect?  I'm really at wits end here, as 35 mph (true top speed, de-restricted) just won't cut it on most roads the way the cagers speed.  Thanks.

Rod

[MMSS]

What you could do to improve performance is take the restrictions off the stock pipe. That way you would have a way better response on aceleration, and perfectly cheap(not so easy xD). If you really want that pipe very badly, just get a similar one to the MRP and try adapting it, although I warn you that it doesnt always work. I have an adapted yasuni pipe, that works perfectly, but I was just lucky...

Hope I helped
MMSS

[harry]

sorry i missed your post ...if you want the pipe go for it  yes it does
 make more noise but you get more top end especially with a kit.
as for the cylinder kit buy the molissi  its best
the kit will give you more low end power and only about 3-7 mph on the top end
 the sound will be lots deeper even with the stock pipe
you can buy both parts from my site  whidbeyparts.com
 burnsy0330  & mmcmaster both have bought pipes from my site

oilyhans

[red-r50x]

Sounds Cool i'm thinking about doing some upgrades myself and i was wounding what jets did you order and how much was the 70cc kit, the mrp pipe, and jets?  That is all ther mods you have didi to your r50x?