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Discussion Starter · #1 ·
Dear All,

First of all let me introduce myself,

I own a Msx since February, i was a very first one to buy this bike since i'm an expat living in Bangkok and i went to buy it as soon as i could after seeing it in a shop (which of course had only 1 bike for show but wasn't selling it!!)

I'm very glad with the bike, I've done almost 7,000 Km in Bkk since (and around) without a single problem, as for all Honda's, except small crash into a Toyota Hillux but that's an other story !

Now i have a couple of questions, i'm definitely not a mechanics, never practiced and i believe that you guys will be able to help me, on the other hand if you have any question regarding the bike i'll be glade to answer it, i'm starting to know it pretty well.

*First question, i'm really starting to consider of upgrading the exhaust : What is your option (without talking about the price), should i go for a Tyga, a LeoVince (Cobra), a Yoshimura or akrapovic ?

So far i love the sound of the Tyga and LeoVince but not sure about the perf.

*Secondly, i've read that we could mount a KN Air filter on the bike, is that correct ? This model : R-1100 - K&N Universal Air Filters, Universal Rubber Filter direct from K&N what improvements can we expect with that ?


*In 6 months i can tell : the front brake is simply a piece of *** it works well if you don't go faster than 70 kmph, after that speed any emergency brake is quite dangerous, the brake is so soft (the rear brake is doing the job properly) :
What could i do to improve it, should i change the Caliper, if so what brand / model should i use ? Also and except Kitaco is there any other brand who made some alternative Brake pads ?

*Is there any interest to upgrade the ECU / Injector with the original cylinder / piston ?, what about changing the valve by setting the one available from Yumimashi ?

*Last question, except air filter and exhaust, without talking about light bore kits, what else could be changed in order to improve the performances ?

Thanks all for your help, and once again, i'll answer to any question if i can.
 

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without opening up the engine there isn't much you can do to really increase performance.

Even a filter and exhaust is only going to do very little to improve performance.

Thank you for your insight on the brakes. I will take note that the brakes are not that good. I think I've seen a rear caliper upgrade but not sure if I've seen the front. Maybe when we get the GROM we will see some bigger front brakes and better brake pads from the aftermarket.

Welcome to the forum and I'll be the first to say = "you lucky ****!! :D "
 

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Discussion Starter · #3 ·
Hi !

Thanks for your fast answer, appreciated !

Regarding the brakes, it's the main problem of the bike, basically the rear brake is too powerful, or i should say that we don't really feel the braking, making sometimes lock /slide.

The front brake is way too soft, especially when you drive in a city like Bangkok you must be confident in your front brake, you get some fellas "cut in front"quite often and when you are stuck between 2 buses and a Toyota hilux XL you have no option that giving all you have in your front brake.

An other "problem" with the bike is the stock tires, they are "ok" on dry but under the rain its the worst tires i never had, so freaking scary believe me especially in Asia, when it rains : IT RAINS !!

Since I've replaced them with some Pierelli Diablo and i feel so good with these new tires !!!!! unbelievable i'm not **** on me when it rains in Bkk.

The main reason why i don't want to touch the engine is that first i can't speak Thai and mechanics here can't speak English at all, then i have absolutely no trust in the mechanic there, had so much trouble before.
 

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Hey Pepper,

Save your money on the air filter - its a waste of money in my opinion.
For the exhaust i would recommend a yoshimura or a dual exhaust system. I am actually glad i went with the dual exhaust as it really sounds like a ducatti now.

I have quite the opposite experience with the brakes. My rear brake does nothing, like absolutely nothing so i have to use the front break which almost causes me to flip over. I will be at the dealer tomorrow and find out about a proper break set.
Since you are in bangkok you should contact 'mad-max-bangkok' and 'xpseed bangkok'. They both have tons of parts for the MSX.
 

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Discussion Starter · #5 ·
Hi,

Hell what you just said about your brakes is so weird !?

Regarding the exhaust i have to say that the dual exhaust systems looks good on the msx but i doubt about the performances gains ? I've heard some pretty bad things about dual exhaust on this kind of engines.

Have you head the tyga slip on, it sounds so great it's amazine, sounds way better than Yoshi so far : [ame=http://www.youtube.com/watch?v=152nXYeIflw]Honda msx 125 fitted with tyga carbon exhaust - YouTube[/ame]

Thanks for the addresses, i already know (from internet) both of these shops, one question : Do they have some qualified mechanics working there ?
 

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This is from my experience with my 1987 YSR-50 cc 2 stroke when I got it back in 1987. To increase HP I first got a Tooney pipe system, Then I got the thin copper head gasket to increase compression, I then did some mods to the air box like drilling about 8 vent holes and putting in button type filter unit. I also put a barnett clutch system and springs. I also changed the counter sprocket, can't remember if I went up a tooth or down a tooth, last item was change the jetting on the carb. With all that changes I got real 70 mph on that 50cc engine.

So as for the GROM/MSX-125 I assume the pipe change going full pipe and cans will increase hp maybe 2-3 hp, plus re-mapping the FI should help out after the new pipes are put on. Air-box should help out with a different filter element so the test would be is to do all the STOCK testing first than slowly change one item at a time and check for any HP gains/ speed time gains and top speed gains. I think going up 150 cc would be more than enough which would give you good HP and fuel mileage. I think most HP gains will be if you port and polish the heads and do a re-map of the FI system. If the head gasket can be changed for a thinner racing copper one with out the piston hitting the heads or intake/exhaust valves then that would be another option to increase compression. Changed gas octane to higher level 91-93 octane from 87 octane.
 

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What bad things did you hear about the dual exhaust systems?
Don't expect any performance gains from a slip on exhaust on the MSX.
I got a full system and i (think) didn't gain anything.. acceleration is the same and top speed is somewhere between 110-112km/h.
 

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What bad things did you hear about the dual exhaust systems?
Don't expect any performance gains from a slip on exhaust on the MSX.
I got a full system and i (think) didn't gain anything.. acceleration is the same and top speed is somewhere between 110-112km/h.
your best bet is to put the MSX-125/GROM in Stock configuration onto a Dyno tester. First ride the Grom for at lease 300-500 miles to get all the internals broken in and wearing in the bearings and valve seating and such. Then put the Grom on the dyno and test for hp in stock form.

then change out the pipes/cans or full system and put it on the dyno and check for HP gains

As you add new performance parts put the bike on the dyno and see if you get any HP changes.

Good Luck
 

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Discussion Starter · #9 ·
Hi,

your best bet is to put the MSX-125/GROM in Stock configuration onto a Dyno tester.
Well thanks for the advice but that is gona be hard to do for me in Bangkok.

What bad things did you hear about the dual exhaust systems?
Well i've heard that to setup a dual exhaust system on a single cylinder engine that small would not lead to any gain and could even in some case make the performance drop.

You said that you'r doing 115 kmph is that on flat road or in a downhill ? (cause i also do 115 but in downhill).
 

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The US models have a catalytic converter in the mid pipe so a full system would be better than a slip-on, not sure if yours has the cat or not. This bike has pretty low compression for this size engine so a stock size higher compression piston could do a bunch for performance. I would not mess with the air box cause you are riding in the rain. Wet air filters don't work very well. Maybe a aftermarket filter in the stock air box once they come out but I would leave the air box in your location.
 

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Haha so true :D I will get that taken care of today. Gotta wait till 11 till my dealer opens then its back to 'grooming' all day :D
 

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I will. I just installed a camshaft from a wave125 today. Little increase in performance but also a weird high pitched sound. Will have the mechanic take a look on monday.
Top speed before was 115 now its 119-120.. but i am also a light weight.
 
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