MNSBR: Super Grom Build - MNSBR

Jump to content

  • 8 Pages +
  • 1
  • 2
  • 3
  • 4
  • 5
  • Last »
  • You cannot start a new topic
  • You cannot reply to this topic

Super Grom Build

#31 User is offline   sk8phreak88 Icon

  • Horse Power is ADDICTING
  • PipPipPipPipPipPipPip
  • Group: Member
  • Posts: 1,571
  • Joined: 18-March 07
  • Gender:Male
  • Location:Coon Rapids
  • Ride:2014 Grom.

Posted 29 May 2018 - 09:59 PM

Been riding my grom lately. My speedo showed 74mph drafting someone the other day on highway 10 on my way to work. But after riding it more often to work lately, Definitely considering this high compression setup after seeing your results and getting some miles on it!
0

#32 User is offline   POE Icon

  • PipPipPipPipPipPipPipPipPipPipPipPipPipPipPipPipPip
  • Group: Moderator
  • Posts: 17,032
  • Joined: 01-February 08
  • Gender:Male
  • Location:Circle Pines
  • Ride:600RR street
    '17 Grom
    '14 Grom
    SV650 race
    YZ250F

Posted 30 May 2018 - 07:48 AM

View Postsk8phreak88, on 29 May 2018 - 09:59 PM, said:

Been riding my grom lately. My speedo showed 74mph drafting someone the other day on highway 10 on my way to work. But after riding it more often to work lately, Definitely considering this high compression setup after seeing your results and getting some miles on it!


73 is the ignition limiter so you must have had a nice draft, haha. In reality, Groms speedos are off a bit just like most motos. But still, that's cookin' on a little machine.

I ran into a problem with the front sprocket. The Grom has a retaining plate that holds the front sprocket to the shaft. It uses two small bolts to keep the retaining plate in place. The sprocket I bought had the wrong bolt hold spacing. It was 34mm bolt hole separation where I needed 30mm. When I went to install and discovered that (Saturday) I was pissed. I almost threw the sprocket across the room. But the correct one will be here tomorrow. So hopefully I'll be breaking in my motor tomorrow night or Friday.

I also got my Straight Up Pump high flow Takegawa oil pump with pickup line delivered finally (it took about a couple weeks). So I'll throw that in, too. Should only take 20 minutes. But it doesn't have a screen to put around the pickup line. So I might just run some break-in oil through the motor for 100-200 miles and then put the new pump in.

I bought an oil cooler too. So I'll have to fab up a mounting plate and then I can install that at the same time as the new pump after some break-in.
0

#33 User is offline   Kent Larson Icon

  • shut up and ride
  • PipPipPipPip
  • Group: Member
  • Posts: 616
  • Joined: 18-June 15
  • Gender:Male
  • Location:Minnesota
  • Ride:WR250R, FJR1300, RC51, RS50

Posted 30 May 2018 - 09:53 AM

I was paying a little more attention to things on my last stock setup Grom commute.
64mph indicated at about 8600 rpm when tucked in a little on the flat.
71-72 indicated at about 500rpm past redline when full tucked and drafting.

Can still match pace with most of the boxes traveling highway 94 but it's an effort.

Later,
Kent Larson in Woodbury
0

#34 User is offline   POE Icon

  • PipPipPipPipPipPipPipPipPipPipPipPipPipPipPipPipPip
  • Group: Moderator
  • Posts: 17,032
  • Joined: 01-February 08
  • Gender:Male
  • Location:Circle Pines
  • Ride:600RR street
    '17 Grom
    '14 Grom
    SV650 race
    YZ250F

Posted 30 May 2018 - 10:15 AM

View PostKent Larson, on 30 May 2018 - 09:53 AM, said:

I was paying a little more attention to things on my last stock setup Grom commute.
64mph indicated at about 8600 rpm when tucked in a little on the flat.
71-72 indicated at about 500rpm past redline when full tucked and drafting.

Can still match pace with most of the boxes traveling highway 94 but it's an effort.

Later,
Kent Larson in Woodbury


Have you GPS'ed your speeds? I did, but it's been so long I can't remember the indicated vs actual spread.
0

#35 User is offline   POE Icon

  • PipPipPipPipPipPipPipPipPipPipPipPipPipPipPipPipPip
  • Group: Moderator
  • Posts: 17,032
  • Joined: 01-February 08
  • Gender:Male
  • Location:Circle Pines
  • Ride:600RR street
    '17 Grom
    '14 Grom
    SV650 race
    YZ250F

Posted 30 May 2018 - 10:18 AM

That reminds me, I installed my new speedo healer on the Super Grom. I'll have to set that up after I'm done with the initial engine break-in laps around the lake. I'll have to maintain speed for a minute or two and compare to GPS, then do some simple math and program the little one-button computer chip. It's cool how much stuff you can do on a chip with only one input button. This is my first speedo healer. I'm probably more excited about it than I should be.
0

#36 User is offline   Kent Larson Icon

  • shut up and ride
  • PipPipPipPip
  • Group: Member
  • Posts: 616
  • Joined: 18-June 15
  • Gender:Male
  • Location:Minnesota
  • Ride:WR250R, FJR1300, RC51, RS50

Posted 30 May 2018 - 10:21 AM

View PostPOE, on 30 May 2018 - 10:15 AM, said:

Have you GPS'ed your speeds? I did, but it's been so long I can't remember the indicated vs actual spread.


Nope. The only thing I have is passing the HEY!-you're-going-too-fast radar station on my way to the highway. It has been a bit but I think I remember seeing 46mph on the sign while trying to hold 50mph on the speedometer.

Next time I pass it I'll try to get a new reading. Can my iPhone do well enough for a GPS? Maybe I'll look into that too.

Later,
Kent Larson in Woodbury
0

#37 User is offline   POE Icon

  • PipPipPipPipPipPipPipPipPipPipPipPipPipPipPipPipPip
  • Group: Moderator
  • Posts: 17,032
  • Joined: 01-February 08
  • Gender:Male
  • Location:Circle Pines
  • Ride:600RR street
    '17 Grom
    '14 Grom
    SV650 race
    YZ250F

Posted 30 May 2018 - 11:07 AM

View PostKent Larson, on 30 May 2018 - 10:21 AM, said:

46mph on the sign while trying to hold 50mph

That would be about right. That's a 6% diff

View PostKent Larson, on 30 May 2018 - 10:21 AM, said:

Can my iPhone do well enough for a GPS? Maybe I'll look into that too.

Should do just fine if you hold a steady speed. As I understand it, phones ping off of wider spread GPS waypoints and take a bit longer, and more distance, to calculate speed. But I have no proof of this and could be totally wrong. I use an app called DigiHud for my GPS speed but have used it mostly in air planes. It's cool to know you're going 568mph to make up time for being 2.5 hours late.
0

#38 User is offline   crakerjac Icon

  • I Should really edit this.
  • PipPipPip
  • Group: Newb
  • Posts: 214
  • Joined: 04-January 13
  • Gender:Male
  • Location:Plymouth MN

Posted 30 May 2018 - 11:57 AM

@POE. Close enough... The GPS in a phone has a data capture rate of 1Hz (one sample per second). For GPS speed purposes, it works just fine.
0

#39 User is offline   POE Icon

  • PipPipPipPipPipPipPipPipPipPipPipPipPipPipPipPipPip
  • Group: Moderator
  • Posts: 17,032
  • Joined: 01-February 08
  • Gender:Male
  • Location:Circle Pines
  • Ride:600RR street
    '17 Grom
    '14 Grom
    SV650 race
    YZ250F

Posted 30 May 2018 - 12:00 PM

View Postcrakerjac, on 30 May 2018 - 11:57 AM, said:

@POE. Close enough... The GPS in a phone has a data capture rate of 1Hz (one sample per second). For GPS speed purposes, it works just fine.


Ah, that makes all the sense. Thanks for clarifying!

Posted Image

0

#40 User is offline   POE Icon

  • PipPipPipPipPipPipPipPipPipPipPipPipPipPipPipPipPip
  • Group: Moderator
  • Posts: 17,032
  • Joined: 01-February 08
  • Gender:Male
  • Location:Circle Pines
  • Ride:600RR street
    '17 Grom
    '14 Grom
    SV650 race
    YZ250F

Posted 12 June 2018 - 08:55 PM

Turns out this "Super 125" build is underwhelming.... So much so, that I'm wondering "what did I do wrong?"

I started this build fresh with 15/35 gears(0/+1), per the recommendation, but I put a 14 on the front immediately after the first ride. I have a 37 on the way to make -1/+3 from the stock 15/34. On my way home from work today, I was going up a small incline, at about 50mph, in 3rd gear, at 9k rpm, and I was not accelerating. I actually was losing speed slowly. And this was not really a hill, just a slight incline. On flat ground in 4th gear I can not accelerate in any RPM unless it's 10-11k+. Seems like 4th gear is just for holding current speed (at WOT). (note: remember the new ECU has 12.5k redline, unlike 9.5k stock)

I'm running a stock air box with all the narrow snorkels removed, a Koso high-flow air filter, a larger diameter intake tube from air box to throttle body, then the Super 125 kit and a Hindle exhaust with the optional baffle installed.

My next step is going to be removing the air box and exhaust baffle and going for a rip to see if changing air flow that much has any major influence.

I'm not sure what else could be wrong. I have been wondering if the intake and exhaust valve rocker arms could have possibly been swapped. Not sure if it would even run that way or not. I opened up the left case and removed the flywheel a second time after installing the Koso tensioner, just to make sure it was tight and moving freely (they can be over-tightened and not move freely). I triple checked timing position. Been using 91oct (for the high compression piston) and this most recent tank has 91 non-oxy. I wonder if it needs 93? I don't hear any knock, though. I have put at least a couple hours on it now. I can't imagine much break-in is necessary.

The guy that sells the kit is now saying that he told me not to buy the cheaper reflashed ECU, which is BS, he said I would be just fine but I could get 1hp more by spending big money on a programmable fuel controller. I'm not sure if I want to part out and switch to a BBK or just spend the money on the controller to see what happens. First thing first, I'll want to verify I have the rocker arms in correctly and the bike is not limited by the air box or exhaust baffle. Now I have an excuse to buy the bore scope I've wanted so I can peak at the rocker arms without taking out the cam.
0

#41 User is offline   Kent Larson Icon

  • shut up and ride
  • PipPipPipPip
  • Group: Member
  • Posts: 616
  • Joined: 18-June 15
  • Gender:Male
  • Location:Minnesota
  • Ride:WR250R, FJR1300, RC51, RS50

Posted 13 June 2018 - 08:28 AM

Sorry to hear the sad results. Good luck sorting everything out.

I'll always have a bone-stock Grom (the wife's) if you want to borrow for comparisons.
If I do a Grom build, I'll need to buy a 2nd one (pre-wrecked for savings, if possible) as my wife doesn't want a thing touched on "her" Grom.
(I think she puts on about 1 mile for every 100 I clock)

Later,
Kent Larson from Woodbury
0

#42 User is offline   crakerjac Icon

  • I Should really edit this.
  • PipPipPip
  • Group: Newb
  • Posts: 214
  • Joined: 04-January 13
  • Gender:Male
  • Location:Plymouth MN

Posted 13 June 2018 - 08:33 AM

Do you notice any improvement over stock? I've been waiting to see if someone comes out with a better head for a 'Super Z125' build (not holding my breath)... but was really hoping this would give the Grom a kick in the shorts.
0

#43 User is offline   ludedude Icon

  • EDITED!
  • PipPipPip
  • Group: Newb
  • Posts: 248
  • Joined: 24-August 06
  • Gender:Male
  • Location:Crystal
  • Ride:R3, 09 zoooooma

Posted 13 June 2018 - 09:53 AM

Is the reflashed ECU map set up for stock airbox or expecting more air through an intake?

Had an issue kind of like this with a build I was doing on the Zuma. I have the ability to tune it with a tuner but the stock intake I was running and non-high flow exhaust choked the motor up top. In the end, not worth it since I wanted to keep stock airbox.
0

#44 User is offline   POE Icon

  • PipPipPipPipPipPipPipPipPipPipPipPipPipPipPipPipPip
  • Group: Moderator
  • Posts: 17,032
  • Joined: 01-February 08
  • Gender:Male
  • Location:Circle Pines
  • Ride:600RR street
    '17 Grom
    '14 Grom
    SV650 race
    YZ250F

Posted 13 June 2018 - 11:05 AM

View PostKent Larson, on 13 June 2018 - 08:28 AM, said:

if you want to borrow for comparisons.

I already have a 2nd Grom that has a stock motor :D Thanks for the offer, though!

View Postcrakerjac, on 13 June 2018 - 08:33 AM, said:

Do you notice any improvement over stock?

Yes, it is still better than stock by at least a small degree. But definitely not as advertised.

View Postludedude, on 13 June 2018 - 09:53 AM, said:

Is the reflashed ECU map set up for stock airbox or expecting more air through an intake?

Had an issue kind of like this with a build I was doing on the Zuma. I have the ability to tune it with a tuner but the stock intake I was running and non-high flow exhaust choked the motor up top. In the end, not worth it since I wanted to keep stock airbox.

No
I took the primary snorkel and secondary snorkel out. The primary snorkel sits on top of the exterior of the box. The secondary is inside the box and behind the air filter. The air box inlet is now a wide open ~2" hole. The new intake tube that connects air box to throttle body is almost just as wide.

I'm not sure when I'll have time to remove the airbox cover and exhaust baffle for testing, but that's high on my list.

1. Check spark plug (tonight)
2. Run with no airbox cover or exhaust baffle
3. Remove cam and rocker arms to inspect proper installation.
4. Buy a new expensive fuel controller (price gouging motherfuckers)
0

#45 User is offline   nOOb Icon

  • I Should really edit this.
  • PipPipPip
  • Group: Newb
  • Posts: 152
  • Joined: 23-May 08
  • Ride:1:12 ZX-6R

Posted 13 June 2018 - 03:26 PM

Yea the unfortunate thing is that a fuel controller and its other components costs just as much as the kit itself. Are you sure the stock O2 sensor is sufficient?

I'm tempted to just run a BBK if I'm spending $500+ on a fuel controller and wideband sensor.

FYI, ebay runs 15% and 20% coupons every now and then. I stocked up on few Grom parts last week when they had the 20%.
0

Share this topic:


  • 8 Pages +
  • 1
  • 2
  • 3
  • 4
  • 5
  • Last »
  • You cannot start a new topic
  • You cannot reply to this topic

1 User(s) are reading this topic
0 members, 1 guests, 0 anonymous users