Honda Grom banner

41 - 55 of 55 Posts

·
Registered
Joined
·
884 Posts
Trying to figure out how to get the best of both worlds (low response and high rpm performance). The only way that I see is if I get head port service, and flat top piston. I'm trying to make this 125cc scream.
Screaming engine is the road most travelled, so there is plenty of advice here on how to do it right. :) Higher compression will get you more power everywhere for sure, although it adds more stress on rod crank and bearings and you'll need to run premium fuel. Porting will definitely improve flow. If you go the tb cam route like everyone else, you'll exchange low rpm torque for high rpm horsepower. That's a trade everyone here is happy to make.

For how I use my Grom, I like an engine that pulls strong from 3,500 rpm and does 26 mph in 4th gear without lugging. I almost never pin the throttle, the engine rarely goes over 7,000 rpms unless I'm doing 55, and it does that easy without full throttle. The bike has absolutely NO problem keeping up with the vehicles around it without needing to spool up the engine. It's a joy to ride. :)

The Grom is not a high performance motorcycle... unless you want to make it into one. ;)
 

·
Registered
Joined
·
884 Posts
Read this on facebook this morning...

"Corey Yates
i wouldn’t do the cam until the bbk.
I have two Groms and the one with just a tb cam is too gutless down low.
And thats even with the ren motowerks hi compression stock bore piston
and tons of other upgrades.

People pretend the grom doesn’t spend much time down there but it does."


 

·
Registered
Joined
·
319 Posts
Trying to figure out how to get the best of both worlds (low response and high rpm performance). The only way that I see is if I get head port service, and flat top piston. I'm trying to make this 125cc scream.
We will have a kit with our high comp piston, tb cam, and reflash here in the next month or so. It should bring back some of the low end torque, but will require a minimum of 91 octane fuel.
 

·
Registered
Joined
·
319 Posts
Read this on facebook this morning...

"Corey Yates
i wouldn’t do the cam until the bbk.
I have two Groms and the one with just a tb cam is too gutless down low.
And thats even with the ren motowerks hi compression stock bore piston
and tons of other upgrades.

People pretend the grom doesn’t spend much time down there but it does."


Everyone is different. The TB cam and flash combo has been one of my best sellers and if you drop down to a 14t it makes it very rideable in my opinion, especially if you're one of those that likes to ride WOT everywhere.
 

·
Registered
Joined
·
884 Posts
Everyone is different. The TB cam and flash combo has been one of my best sellers and if you drop down to a 14t it makes it very rideable in my opinion, especially if you're one of those that likes to ride WOT everywhere.
I totally agree. :)
The well thought out products you offer exactly fit the riding style of your customers.
 

·
Registered
Joined
·
115 Posts
I just bought a dinger built mid and a Yosh ST-1M cam (already have the Yosh RS2). I guess I need a flash (until the AR mini 5 goes on sale - never) before I install.
 

·
Registered
Joined
·
499 Posts
Discussion Starter #47
We will have a kit with our high comp piston, tb cam, and reflash here in the next month or so. It should bring back some of the low end torque, but will require a minimum of 91 octane fuel.
I went and got your tb cam, and reflash deal during the summer. The bike runs great and everything, but I'm looking for more flow, and a port job should do the trick. I'm interested in the high comp piston whenever it's available. Is a reflash needed for the high compression comp? I may have to send in my head for a port job from you guys. Keep us updated!
 

·
Registered
Joined
·
2 Posts
I did a round of upgrades last weekend from completely stock, to adding a Yoshimura rs-2 exhaust, dinger built short intake, TBolt cam, and DH motoring ECU. There was a noticeable loss of low end power, particularly when starting from a stop. However, there is certainly more power above 7k rpm. I encounter one hill on the way to work, where I get knocked a couple mph below the speed limit, and I'm confident these upgrades will give me that few extra.
 

·
Registered
Joined
·
884 Posts
I did a round of upgrades last weekend from completely stock, to adding a Yoshimura rs-2 exhaust, dinger built short intake, TBolt cam, and DH motoring ECU. There was a noticeable loss of low end power, particularly when starting from a stop. However, there is certainly more power above 7k rpm. I encounter one hill on the way to work, where I get knocked a couple mph below the speed limit, and I'm confident these upgrades will give me that few extra.
Your experience is totally normal. Most riders wind their engines out all the time so the TB cam is perfect for them because the lobes are profiled for high rpm performance. Everything is a trade off. To gain high rpm horsepower you have to give up low rpm torque.

My engine is totally the opposite. My Grom is not fast. There's absolutely nothing over 7,000 rpm (~55 mph). I don't even bother trying to go past there as that's more than fast enough for all of my uses. However, I can climb our 12% grade driveway at 3,000 rpms without lugging the engine, so low rpm torque is perfect for me as it makes my Grom really pleasant to putt around on. :)
 

·
Registered
Joined
·
190 Posts
I did a round of upgrades last weekend from completely stock, to adding a Yoshimura rs-2 exhaust, dinger built short intake, TBolt cam, and DH motoring ECU. There was a noticeable loss of low end power, particularly when starting from a stop. However, there is certainly more power above 7k rpm. I encounter one hill on the way to work, where I get knocked a couple mph below the speed limit, and I'm confident these upgrades will give me that few extra.
Longer intake might make a difference in the low end I expect.
 

·
Registered
Joined
·
75 Posts
We will have a kit with our high comp piston, tb cam, and reflash here in the next month or so. It should bring back some of the low end torque, but will require a minimum of 91 octane fuel.
I've been trying to find the info online, but don't see any specific numbers. What is the compression ratio of your piston?
 

·
Registered
Joined
·
2 Posts
I did a round of upgrades last weekend from completely stock, to adding a Yoshimura rs-2 exhaust, dinger built short intake, TBolt cam, and DH motoring ECU. There was a noticeable loss of low end power, particularly when starting from a stop. However, there is certainly more power above 7k rpm. I encounter one hill on the way to work, where I get knocked a couple mph below the speed limit, and I'm confident these upgrades will give me that few extra.
My Grom was stolen last night. Literally rode the bike once with these mods.
 
41 - 55 of 55 Posts
Top