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Discussion Starter #41
So another update. I got the motor back into the frame on Monday and got all the wires reconnected. I also redid the crank case venting system. Using the GromFatherz vented crank cover, some silicon hose, a brass T-fitting, a UNI breather filter, a vacuum nipple cover, and some zip ties.







So the airbox CCV port is capped now. The GromFatherz cam cover goes to a short section of hose and meets the T-fitting. The straight section goes up the UNI breather filter and the T part goes to the stock CCV hose from the clutch side of the motor. The UNI filter sits in the tank cutout where the stock airbox snorkel sat.

The motor started on the first crank really quickly, I rolled it out to the end of the driveway to let it come up to temperature before the maiden voyage. I get geared up and ready for the first ride. Slowly let the clutch out and it grabbing smoothly no issues. I do notice I need to give it some more revs to get going, that lightened oil spinner definitely kills some of the flywheel effect of the stock heavy oil spinner. I accelerate slowly and bring the revs up to about 6k and pull the clutch, I toe at the shifter and NOTHING, the transmission wont shift. I try for a few more minutes to no avail. I can get into neutral, but it wont shift to second gear. At this point my mind is racing, I must have fucked up the transmission install. I get the bike back into my garage and start checking over everything I can think of externally. The clutch adjustment felt really good, but I gave it another look over and it seemed good. The next thing I check are the shift linkages to see if anything is binding up. Fuck me sideways, I had installed the shift arm one spline off from where it should have been installed. I get back to the end of the driveway and the motor easily fires up again. Pull out into the street, pull the clutch and toe the shifter, click, right into 2nd gear, a little rougher than I would have liked. Let's try that again, click, into 3rd, still rough. I clicked into all the gears a little rough, but it shifted, better that the first try. I turned around and started again, wait that shift was a lot smoother. After about the 5th time shifting up though the gears it shifted like butter. I have never felt the Grom transmission shift this smooth before. The stock Grom transmission is a bit clunky at best and leaves a lot to be desired. The Takegawa shifts like a big bike transmission, smooth and very positive. Lets try it with the QS now, WOW, it shifts so much quicker and smoother between 1st and 2nd now. It feels a lot like my R6 now. The stock transmission would kind of clunk into 2nd gear and take forever to shift, and you would get an occasional false neutral. Its so smooth, precise, and fast now. I can probably speed up the QS kill time about 10-15ms. I'm wondering how much of this buttery smooth shift action is attributed to the Takegawa transmission or the Factory Pro shift kit? I have not encountered in a single false neutral or missed shift since I got it back up and running.

I'm a firm believer of the hard break in method for engines, I put about 40 miles on it since starting it back up and after a few laps around the neighborhood I started ragging that ass hard. The motor pulls hard all the way past the end of the tachometer, before it bumps the limiter, it sounds mean as hell doing it too. The extra power from the motor and the superior gearing just combine to make the Grom pretty quick from a stop or from slower speeds. The one weird thing I noticed is that in 4th gear the speedometer always seems to just start reading zero for some reason. I installed the provided washer between the case and the speed sensor, has anyone encountered this issue?

Sorry about the wall of text.
 

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Discussion Starter #42
I got the speedometer cutting out in 4th gear issue solved. I ended up pulling the washer between the case and the speed sensor out completely and 4th gear reads perfectly now. I pulled the sensor after going out for a few hours and there were no marks on the pickup.

I put about 120 miles on the new motor so far and just did the first oil change, just a spill and fill, no spinner cleaning. I did have a lot of ferrous material on the magnetic oil drain plug, but that's to be expected out of a new motor and transmission. I'll do another oil change at the 500 mile mark and I will pull the clutch cover and clean out the spinner and oil strainer.

For those wondering about the FactoryPro shift kit, I think its worth it. Since installing everything the transmission has never shifted so smoothly and positively, and I have not encountered a single false neutral. I would have the transmission pop out of 2nd gear every so often when using the quickshifter but I have not had it happen since, and I've been beating on it pretty hard. We will see how well it all holds up over the course of this racing season, but it all looks promising so far. Neutral is still difficult to find lol.
 

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Discussion Starter #43
I decided to try something different with the clutch springs and swap out 3 of the SMR +30% springs for 3 of the Kitaco +60% springs. It should effectively be a 45% stiffer setup if my math is correct. I definitely like the feel of the stiffer clutch lever and call me crazy but it feels like its easier to control. The slipper clutch still functions really well, I was concerned the extra spring pressure might impede the slipper clutch action, no issues there.







I also cleaned the spinner which had a nice layer of sludge built up and the mesh strainer which also had some metal shavings in it. I put another 30 miles on it today and the transmission shifting seems to be getting even smoother, I don't know if it's the gears just wearing in together or the fresh oil is making it feel smoother, probably a little bit of both.
 

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Good to know about the FP shift kit. My 5 spd likes to find a false neutral between 3 and 4.
 

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Discussion Starter #45
Good to know about the FP shift kit. My 5 spd likes to find a false neutral between 3 and 4.
It's hard for me to really give an exact impression of how good the FactoryPro kit works by itself. I'm mainly going off of how the stock transmission felt compared to now. The Takegawa 5 speed with the shift kit, shifts considerably smoother and faster.
 

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Discussion Starter #46
I did my first track day of 2020 on Saturday. The engine and transmission ran great, no issues there. I do have a minor rear suspension squeaking issue which I think might be shock related. Early sessions weren't that confidence inspiring, it was a cold track and I had the tire pressures too high. Once the track temps started to warm up and I got the tire pressures dialed in, I started pushing it harder. It still needs a bit more tweaking, but its getting closer.

On a side note I got my number plates for this season from Seventy Seven Decals, they came out great and he gets them done quick. I would say you need a heatgun and make sure you clean the surfaces really good and the end product will look awesome.







 

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Discussion Starter #48
As a photo / video buff, let me just say I appreciate the crisp camera work....
I'm not a great photographer by any means, but I try to make them as clean as as possible. I can't stand seeing pictures online that look they they were taken with a potato. Cell phone cameras these days are amazing, and I'm using an 'older' Pixel 2.
 

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Thanks for the video, enjoyed it.
 
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Discussion Starter #52
I took a deep plunge ya'll, I ponied up for a set of BST wheels and PMT slicks. Too bad we're all on lockdown and can't even test them out on the track. I'll get these mounted up and balanced in the next few weeks, I'm looking forward to seeing if this combo lives up to the hype!

















I also was having issues with my battery, mostly since the motor build. I think the battery was just losing cranking amps due to its age, being stock from 2015, and combined with the high compression piston and no decomp on the cam anymore. I picked up a Antigravity ATZ-7 lithium battery, mainly for the small weight savings and the higher CCA. It saves a hair over 2lbs over the stock battery and has double the CCA of the stocker as well.





The bike starts up WAY stronger than it did on the stock battery with the motor build, it's hard to feel a 2lb difference though lol.
 

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Wow, I'm excited to hear your opinion on the rims and tires. Hope you post a video of the next track outing!
 

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Discussion Starter #54
Wow, I'm excited to hear your opinion on the rims and tires. Hope you post a video of the next track outing!
Yea I'm pumped to see how these things perform. I actually just got invited to a last minute private track day for less than 10 people. Problem is, it's tomorrow and I won't be able to have everything installed in time. I'm just happy to get out of the house and on the track for a few hours. I'll definitely be doing some recording of the day.
 

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False neutral is any neutral besides actual neutral between 1st and 2nd.

Please let me know what you think of the BSTs. I'm considering a set as well.
 

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Any updates on the BST wheel performance?

Have you noticed any significant changes in acceleration due to the reduced rotating mass?

Does braking feel different?

Overall handling changes?
 

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Discussion Starter #58
Update time! It's a big one this time around.







I mounted up my BST wheels a few weeks ago and had two trackdays out on them. I can firmly say the gain on these these wheels and tires is REALLY impressive. The bike accelerates quicker and transitions corner to corner, full lean to full lean so quickly and easily. If you thought the Grom steered fast before, its even lighter and faster now, it's really silly. The corner speeds and grip level with the PMT slicks have gone up considerably, if I had to put an arbitrary numerical figure on it, at least 15-20%. The total gain with the new wheels and tires combined is amazing. These wheels are NOT cheap, but if you're into doing trackdays and racing then they are completely worth it.









I got a set of Composimo RaceBarz because I wanted to get lower and further forward to get a bit more weight on the front end. These things are top notch quality and are awesome on the track. The kit uses Woodcraft risers and clip ons which are some of the best you can buy. The machined bar adapter is is also very nicely finished, nothing but praise for the quality of the kit. I like the position the clip ons get my body into, but I ran into another problem/limitation of the Grom platform with my lower body and legs which I will be addressing in another post in the future.
 

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Discussion Starter #59






























I ordered a G'Craft swingarm from Webike and got it fully optioned out exactly how I wanted. Triple Square tube, standard length, with spool bosses, bolt on chain slider, OW type chain adjuster, OEM fender brackets, and most importantly the bearing pivots. Also picked up the superbike style lifters for the hell of it. This thing is beautiful, it's goddamn work of art, functional bling to the max. The swingarm saves weight, it should be much stiffer than the stock swingarm, and the bearing pivots are ridiculously nice. The swingarm literally has no drag on it whatsoever when the pivot bolt is torqued down to spec. I had to adjust my shock damping quite a bit to get it right again. I have not had it on track yet, but I will soon

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These are videos from the last two trackdays I did with the new wheels and slicks. I think I did a decent job of fending these guys off for a while considering I'm down on power and/or up on weight compared to these guys. I'm just having a hell of a time enjoying my Grom.
 

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Amazing mods, and fantastic photos and documentation!

Oh, and yeah, nice riding!

What kind of tire changer is that you have pictured? Link to where you got it?
 
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