GromForum.com banner

1 - 20 of 25 Posts

·
Premium Member
Joined
·
719 Posts
Discussion Starter #1
So when you change the exhaust, add a big bore kit, or intake. What do you do about fuel, injectors, tuning, etc?
Are there maps? Can we tube with a laptop? Is it like a fiddy with a CDI box swap?
I need intake, exhaust and big bore on mine. Maybe a stock one too. Lol
 

·
Registered
Joined
·
74 Posts
Efi tuning

I sent an e-mail to the customer service at electronicjetkit.com, but they havent replied. I believe their controller should work with the EFI on the grom. In july, once i get the new cam and 150 light bore kit installed, i will give them a call and see if they can get the right connectors for it so i dont have to splice any wires. Here is a pic of the o2 sensor. Once i get it all working in a few months ill post the results.
 

Attachments

·
Registered
Joined
·
74 Posts
Pic of the grom throttle body

You can see the Injector, TPS, and i believe the MAF sensor here. The temp sensor (not shown) is on the bottom side of the head and reads the oil temp as it flows through the gallery.
 

Attachments

·
Registered
Joined
·
74 Posts
I know there are two different types of recommended grom spark plugs, one for regular riding and a higher performing one for extreme riding and probably even for when you do mods like an aftermarket exhaust just to help even things out better. I'll try to find the spark plug number on that.
 

·
Registered
Joined
·
1,621 Posts
How are the guys in thailand doing it? I don't think I've seen any MSX 125s with the bore kit yet.
 

·
Registered
Joined
·
64 Posts
How are the guys in thailand doing it? I don't think I've seen any MSX 125s with the bore kit yet.
tried looking and seems like no one has one of the bore kits yet
might be best if someone gets in contact with yuminashi to see what's the status on their bore kits.
 

·
Premium Member
Joined
·
292 Posts
The dealer selling me my MSX125 today (UK) said he could get a 150cc and a 180cc conversion. I understand, but stand to be corrected, that the fuel injector is replaced by a carb. on the 180cc as the EFI cannot be changed.

He mentioned a dealer on the Isle of Man is importing MSX tuning gear from Thailand as well, which, if correct, will save on postage!

I ordered a rear luggage rack from Bikerzbits for USD75 delivered to the UK which is not too bad considering it is by airmail.

Jeff
 

·
Registered
Joined
·
74 Posts
Good news, I just got word from a distributor for yuminashi about 5 minutes ago. The sx30 heads will be in stock in about 3 weeks so in 4 weeks I should have the bore kit and new head. I'll be sure to document the process and post it here, as well as the results, and and pictures. I just got a gopro too so I'll work on getting some videos out in a few weeks.
 

·
Registered
Joined
·
995 Posts
Good news, I just got word from a distributor for yuminashi about 5 minutes ago. The sx30 heads will be in stock in about 3 weeks so in 4 weeks I should have the bore kit and new head. I'll be sure to document the process and post it here, as well as the results, and and pictures. I just got a gopro too so I'll work on getting some videos out in a few weeks.
great, looks like july will be a good month since we'll see your grom build plus many others that get the bore kit.

have you started looking into your exhaust options?
 

·
Registered
Joined
·
995 Posts
Maybe they will make a power commander for the grom once it's out that will be cool
wouldn't be surprised if one is already available seeing how thailand is where the largest MSX125/Grom scene is at the moment, aftermarket support over their is crazy
 

·
Registered
Joined
·
73 Posts
The dealer selling me my MSX125 today (UK) said he could get a 150cc and a 180cc conversion. I understand, but stand to be corrected, that the fuel injector is replaced by a carb. on the 180cc as the EFI cannot be changed.
Yikes so if the injector goes out you have to scrap the entire bike!?? :sarcasm:

This is why you don't take advice from a dealer haha

As far as tuning, any efi controller will do the job you just have to figure how to wire it in.. I personally will probably go with a Kitaco Imap as its what I'm most familiar with having wired one into the same ecu type the MSX/Grom uses
 

·
Premium Member
Joined
·
719 Posts
Discussion Starter #15
I have been building big bore xr50s for years. Carb would be awesome.
 

·
Registered
Joined
·
74 Posts
Engine Upgrade

great, looks like july will be a good month since we'll see your grom build plus many others that get the bore kit.

have you started looking into your exhaust options?
I already have a stainless steel down pipe, once i find a single exhaust i like ill get it.

As far as efi controllers, ill be writing to a few manufacturers to see if any of them are interested in developing one for the msx. The Efi system should, to some extent, automatically adjust itself to maintain the stoichiometric mixture. The problem is, at what point will the injector reach full duty cycle? I think with a mild bore kit it should be fine, but to tune it for maximum hp and torque a controller will be needed with a wide band o2 sensor. I like the idea of the EJK, controller and im sure its possible.
With the engine being so new it seems not many companies have been able to develop maps yet for them, second there is probably little demand now. I believe once peoples warrarties expire is when the demand for the engine mods will really take off. For me i don't care. I bought this think to experiment and play around with.


There is always the option of using a micro-squirt controller and i might use that if nothing else is available. That option would give me max control, but would be a bit overkill for a single cylinder engine.
 

Attachments

·
Registered
Joined
·
73 Posts
The problem is, at what point will the injector reach full duty cycle? I think with a mild bore kit it should be fine, but to tune it for maximum hp and torque a controller will be needed with a wide band o2 sensor. I like the idea of the EJK, controller
Yuminashi has a "150cc bb injector" that you swap in when you go 150, which bumps the fuel delivery up so you aren't maxing out the injector

I do agree some sort of adjustable fuel controller is needed to perfect the afr though
 

·
Registered
Joined
·
35 Posts
Good news, I just got word from a distributor for yuminashi about 5 minutes ago. The sx30 heads will be in stock in about 3 weeks so in 4 weeks I should have the bore kit and new head. I'll be sure to document the process and post it here, as well as the results, and and pictures. I just got a gopro too so I'll work on getting some videos out in a few weeks.
This is interesting to me I really want to get most power out of my bike if I get Grom. Pictures on how would be great thanks. Sammy
 
1 - 20 of 25 Posts
Top