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Accessories!!!! Engine mods!!!! what's the best?

chuckklr98

Member
Joined
Aug 28, 2021
Messages
35
Seat. I like to do adventure rides on little bikes. would like an upgrade good for 8 to ten hrs a day.

Engine mods....Mild for now, but set it up for wild later. (still in warranty). Stuff like swapping injector from bigger engine, removing snorkel, rodding out cat, or removing spark arrester.

Who has done these, what did you use, and what were the results?

BTW, have already ordered aux gas tank, downtube rack, headlight rack with headlight protector, rear seat, magnetic oil plug, and a leather saddlebag. Next up is mirror extensions.
 

dmonkey

Active member
Joined
Jul 4, 2021
Messages
223
Not my video, but this guy tested and observed worse performance from removing the spark arrestor:

An aftermarket exhaust can certainly give you a little performance boost though.
 

m in sc

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Feb 2, 2021
Messages
526
Location
Rockhill, SC
it takes time for the ecm to adjust, a point he neglected to observe.. and was on different days and different conditions.. i pulled my spark arrestor out and it helped a bit. I then de-catted , made a less restrictive headpipe, and added a cam, it helped a bit as well. top speed is a bit better overall but the mid-range and getting -to- top speed and maintaining top speed up hills is much improved. I can hit 60-62. Not earth shattering but better. I think im going to try a 143 kit.
 

chuckklr98

Member
Joined
Aug 28, 2021
Messages
35
it takes time for the ecm to adjust, a point he neglected to observe.. and was on different days and different conditions.. i pulled my spark arrestor out and it helped a bit. I then de-catted , made a less restrictive headpipe, and added a cam, it helped a bit as well. top speed is a bit better overall but the mid-range and getting -to- top speed and maintaining top speed up hills is much improved. I can hit 60-62. Not earth shattering but better. I think im going to try a 143 kit.
Getting the exhaust free flowing must be combined with air flow to carb/throttle body and fuel enrichment/jets/injectors. Which is why I'm asking what is everyone doing.
 

m in sc

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Feb 2, 2021
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526
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Rockhill, SC
not if the exhaust is restrictive in the 1st place, which it is. I told you what i did. it flows fine. Its nowhere near my 1st rodeo. However, to get MORE you need fuel controller, not yet available. at that point, you can them move up to much bigger bores, larger TBs, bigger cams etc. Look at some of my previous posts. On my grom, i could get 95 out of it w a 4v head and a 34mm TB and a BIG hand made SS exhaust, BUT, i had a power commander and open ecu to work with. when THAT becomes available, you're good to go. On this bike, and all the 125 honda motors of this series, a free flowing exhaust does not require a re-map or anything else. The stock ecu can adjust for it. If its too lean, you can then bump up to larger injector (6,8,10 hole etc) to handle the fuel needs, even w the stock TB. If you don't want to take my word for it, reach out to hard Racing, they are very good with answering questions as to whats available and what you can do with these platforms.
 

Msfitoy

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Jan 13, 2021
Messages
300
Location
NC
Not my video, but this guy tested and observed worse performance from removing the spark arrestor:

An aftermarket exhaust can certainly give you a little performance boost though.
He mentioned that he didn't think it gained anything...
 

chuckklr98

Member
Joined
Aug 28, 2021
Messages
35
not if the exhaust is restrictive in the 1st place, which it is. I told you what i did. it flows fine. Its nowhere near my 1st rodeo. However, to get MORE you need fuel controller, not yet available. at that point, you can them move up to much bigger bores, larger TBs, bigger cams etc. Look at some of my previous posts. On my grom, i could get 95 out of it w a 4v head and a 34mm TB and a BIG hand made SS exhaust, BUT, i had a power commander and open ecu to work with. when THAT becomes available, you're good to go. On this bike, and all the 125 honda motors of this series, a free flowing exhaust does not require a re-map or anything else. The stock ecu can adjust for it. If its too lean, you can then bump up to larger injector (6,8,10 hole etc) to handle the fuel needs, even w the stock TB. If you don't want to take my word for it, reach out to hard Racing, they are very good with answering questions as to whats available and what you can do with these platforms.
I'm thinking one size up injector (pch 150?) , remove airbox snorkel, and spark arrester. What ya think? , I don't plan on knee deep water crossings.
 

m in sc

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Joined
Feb 2, 2021
Messages
526
Location
Rockhill, SC
prob work just fine. look up my efie post to help target the correct afr. however, the stock system and injector can take quite a bit. the intake runner is the biggest restriction after the pea shooter headpipe. tbh, and I mentioned this earlier elsewhere, a Yoshimura carb conversion is the most viable at this point to control heavy mod fueling needs on the trail IMHO.
 

m in sc

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Feb 2, 2021
Messages
526
Location
Rockhill, SC
to that point.. I would seriously consider investing in a wide band afr guage to get fueling readings or your going to wind up targeting 14.7 on a hot rodded aircooled commuter motor and you'll cook it. saw it a lot in the grom community early on. .02
 

chuckklr98

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Aug 28, 2021
Messages
35
to that point.. I would seriously consider investing in a wide band afr guage to get fueling readings or your going to wind up targeting 14.7 on a hot rodded aircooled commuter motor and you'll cook it. saw it a lot in the grom community early on. .02
You really think a mild tune will cook it? Throwing more gas in it with a bigger injector should keep it cooler. Would love to have a oil cooler. Only saw one on ebay that looked like it might work, but was for grom. Are the heads that different?
 

m in sc

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Feb 2, 2021
Messages
526
Location
Rockhill, SC
heads are interchangeable. however the ones that feed of the oil studs are junk. you want off the cylinder oil cooling. depends on the mods but at a target of 14.7 regardless of what injector is in there, not much room for cyl temp increases w out melting a piston. hence the need for a fuel controller but more importantly an afr gauge. the 1st thing i did was fit a device to make the 02 sensor lie to the ecm and I now get 13 5-13.8 afr which makes it much safer.
 

SLO

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Nov 26, 2021
Messages
7
Just a little more power to make it safer around unsafe drivers. I am paying attention. It is an air pump after all,and liability and regulations are why there is an issue. I do appreciate the sharing of facts by those that want to help.Thank you! A valuable tool that GOD wants me to ride, cause IT wants to have FUN! When we ride ,( IT ) , GOD whatever one want's to refer it as , GUARDIAN ANGEL whatever, is smiling right along with us when we are motoring around. It is A GODLY ACT to RIDE. GO SLO , cuz SLO is SMOOTH, and SMOOTH is FAST. SLO SEZ ( also known as CAP'N CZY )
 

m in sc

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Feb 2, 2021
Messages
526
Location
Rockhill, SC
im not sure about all that, but IMHO, 55-60 capable is livable when using it on primarily roads as I do. . anything under that is moped area and just a road block to me. .02
 

chuckklr98

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Aug 28, 2021
Messages
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im not sure about all that, but IMHO, 55-60 capable is livable when using it on primarily roads as I do. . anything under that is moped area and just a road block to me. .02
I'm with you on that. Nothing less than 5mph under speed limit cruise speed
 

dmonkey

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Jul 4, 2021
Messages
223
The headlight's no good for me either, at night I pass bicyclists with better lighting 🤦‍♂️ Off-road I've been using the high beam constantly.
I've only found one direct upgrade available, and it looks both sketchy (has a fan to cool the controller unit, not a good sign) and expensive.

Unless someone else has a direct upgrade to recommend, I'll likely install auxiliary lights to supplement the headlight. My state allows up to two of them on a motorcycle.
 

SneakyDingo

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Joined
Aug 6, 2021
Messages
60
The headlight's no good for me either, at night I pass bicyclists with better lighting 🤦‍♂️
Funny you brought up bicyclists, because being that's my primary way of getting around, I've been wondering which of the options I should take: vehicle mounted or helmet mounted.

Mouse McCoy in Dust to Glory had a setup that hooked into the jaw part of his helmet which I really liked. It gave him the ability to point the lights where he was looking, which is useful for reading maps as well (don't use white paper), with the main downside being that you then have to figure out a way to route cables and connect everything up with a quick release connector so you don't clothesline yourself walking away from the bike (or use a battery pack). The Electric Unicycle (EUC) group I'm part of also has a mod that clips to the underside of the visor of the helmet, which will do the same thing but slightly reduce field of view. EUC's can have roughly the same general speed range as CT125's (my Gotway MSX 100V goes up to 47 mph) so I've already battle tested the solution for lighting.
 

dmonkey

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Jul 4, 2021
Messages
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That's certainly an interesting idea. For navigation I've learned from trail runners that having the light source come from too close to your eyes can make terrain look two dimensional, they'll often wear a belt light or carry a very light flashlight in hand because light from that lower height and different angle creates shadows that highlight terrain obstacles when viewed from your eyes that are higher up. I've seen plenty of aux lights mounted on the engine guard tubes on the CT125, but I'm researching options to mount them to the forks, or directly to the left and right of the headlight, so they turn with the bike's steering. Having frame mounted lights is great for straight lines, not so great for canyon riding and trails. I run an adaptive LED headlight on my primary canyon carver, but those headlights are still very high in price for the ones that hold up, and the cheaper ones fall apart with offroad riding.
 
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