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It is good to see you've got things sorted out from the crash.

You mention being in PHX. You've probably met my friends Stephen and Kristine GIllen at a local track day. They live in Avondale. They've both got N300s (Kristine's only for track days), and Stephen also races a Yamaha TZ125 and a Honda RS125 2T GP bikes as well as his AHRMA Honda 160-based vintage twin. He's been one of the fast guys in AHRMA GP200/250 vintage for years on the 160-based bike, and goes quite well on the 125s in SOS3 too. If you see him you should have a chat, they are nice people.

" Me and an R3 battled for position the entire race, he got me in the end but it was extremely exhilarating." Placing well is nice, but I think having someone about the same speed to race with is even nicer. One of the most entertaining races I had was on a borrowed and near stock 160 Honda at Big Willow. My pal David Stark and I battled the entire race to make the other be in last place and it was a hoot. Most of us are not going to be anywhere near a trophy, so getting a good race is about as good as it gets.

cheers,
Michael
 

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Great read, I started at the beginning and read it in its entirety. Welcome to the wonderful world of racing, it sounds like you've spent your money wisely from the start by dropping the bike off at RT. I've used these guys back in the day and they have always done me right so I have one bike with the RT emulators too. Proper suspension setup is key to feeling settled on a bike and giving you the confidence needed to push the bike harder.

You have come a long way and looks like you're on the right track for success as a racer. The upgrades are spot on and the bike looks fantastic. Did you have your leathers repaired or did you replace them?

I do wish I'd seen this write up as I was building my bikes, could have saved me some R&D time. :) Funny how we ended up with similar build choices.

I have just the opposite problem as you though, I am too long for my pegs, I have the Vortex resets on my bike too but they are set as far back and as low as they will go to help with leg room. I have recently added the new GP upper from HotBodies/Norton to lower my clipons even further allowing even more room to stretch out and get better position on the bike.

I do have a suspension question for you that Kiwi touched on early on. A lot of time has gone by since you first reported on your suspension numbers so if you have adjusted the bike since then ignore the following. RT has you on a fairly stiff front set of springs and from watching the video of you celebrating the rebirth of your bike plus your comment of being 5'7" leads be to guesstimate your weight in the 150-160 range. So my question is did RT have you come in and get your sag numbers with you on the bike? If so I am very confused how you would need a .85 kg/mm spring or why they have me on a .7 kg/mm at 170 lbs with barely any preload turned into it with a sag of 32mm. The 46mm of sag in the rear is on the soft side, so from here and on paper ( on screen ) it seems that the front might be too stiff and the rear is soft.

Oh, and low siding on the track is the same way I had my first get off, it ended my season because I separated my collar bone from my shoulder and ended up in a body sling for 4 months. This was just a few years ago June of 1989. 🧓

Enjoy your next track outing you've got to be itching to get a knee on the pavement. Keep posting the videos!!!!!!
 

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I have just the opposite problem as you though, I am too long for my pegs, I have the Vortex resets on my bike too but they are set as far back and as low as they will go to help with leg room.
Tape some sheets of closed-cell foam onto the seat and see if the extra height helps you get more comfortable.
 

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Tape some sheets of closed-cell foam onto the seat and see if the extra height helps you get more comfortable.
I've seen this done as well as adding it to tank forcing the rider to the back of the seat. I will give it a go after one more outing with the new upper. I had a lot less knee pain on my last outing and was able to ride all 6 sessions.
 

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Discussion Starter #106
Great read, I started at the beginning and read it in its entirety. Welcome to the wonderful world of racing, it sounds like you've spent your money wisely from the start by dropping the bike off at RT. I've used these guys back in the day and they have always done me right so I have one bike with the RT emulators too. Proper suspension setup is key to feeling settled on a bike and giving you the confidence needed to push the bike harder.

You have come a long way and looks like you're on the right track for success as a racer. The upgrades are spot on and the bike looks fantastic. Did you have your leathers repaired or did you replace them?

I do wish I'd seen this write up as I was building my bikes, could have saved me some R&D time. :) Funny how we ended up with similar build choices.

I have just the opposite problem as you though, I am too long for my pegs, I have the Vortex resets on my bike too but they are set as far back and as low as they will go to help with leg room. I have recently added the new GP upper from HotBodies/Norton to lower my clipons even further allowing even more room to stretch out and get better position on the bike.

I do have a suspension question for you that Kiwi touched on early on. A lot of time has gone by since you first reported on your suspension numbers so if you have adjusted the bike since then ignore the following. RT has you on a fairly stiff front set of springs and from watching the video of you celebrating the rebirth of your bike plus your comment of being 5'7" leads be to guesstimate your weight in the 150-160 range. So my question is did RT have you come in and get your sag numbers with you on the bike? If so I am very confused how you would need a .85 kg/mm spring or why they have me on a .7 kg/mm at 170 lbs with barely any preload turned into it with a sag of 32mm. The 46mm of sag in the rear is on the soft side, so from here and on paper ( on screen ) it seems that the front might be too stiff and the rear is soft.

Oh, and low siding on the track is the same way I had my first get off, it ended my season because I separated my collar bone from my shoulder and ended up in a body sling for 4 months. This was just a few years ago June of 1989. 🧓

Enjoy your next track outing you've got to be itching to get a knee on the pavement. Keep posting the videos!!!!!!
Thanks, I still have a ton to learn riding wise. Luckily building things is my forte so I don't think I made many mistakes with my build.

I had my Vanson leathers repaired, just patched. However I also got my custom Mithos leathers with techair.



My suspension setup is definitely something I'm starting to target, absolutely nothing has been done since racetech installed it. I was 160lbs when they set it up, they used ballast to set it up. I'm 145lbs now. I've been studying racetechs suspension bible and reading everything I can find about suspension setups. I'm absolutely 100% convinced that the front is to stiff. The front tire is not loading and the bike is understeering hard. You can actually see it in my riding videos. Every time I go out I end up having to drop PSI in the front tire to get it to stop cold tearing. Where as the rear tire is overheating. I first thought this was just my lack of riding technique and not pushing the front hard enough. As I've been working on trail braking, the front is just not confidence inspiring. My number 1 priority after getting 1 day of track time is to get the suspension properly setup. I need to go drag my knee a bit before my bike goes down for maintenance again lol. Also I was 2 months old in June of 89 😅
 

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I've been studying racetechs suspension bible and reading everything I can find about suspension setups.
If you haven't yet get a copy of John Bradley's third volume in the set "The Racing Motorcycle: a technical guide for constructors". Here's a link to the V3 page on his website where you can see a few sample pages:


Volume 3 is entirely on chassis setup. It is available in the US from an Amazon seller at a bit less than what John can do for sending a book from England.

cheers,
Michael
 

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Discussion Starter #108
If you haven't yet get a copy of John Bradley's third volume in the set "The Racing Motorcycle: a technical guide for constructors". Here's a link to the V3 page on his website where you can see a few sample pages:


Volume 3 is entirely on chassis setup. It is available in the US from an Amazon seller at a bit less than what John can do for sending a book from England.

cheers,
Michael
Thanks for recommending a book, I'm definitely going to pick it up.
 

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Nice set of leathers and yes for sure the front is too stiff. My guess is you will need a much lighter spring in the front like a .60 kg/mm. Being down on weight you might actually find that your rear sag numbers will be much closer now than before. 45 mm is too soft for sure but you're down 15 or more pounds from where the bike was setup.

If you're not comfortable doing the sag measurements find a shop or another racer who is. You definitely have the correct components (short the lighter springs) to achieve a well handling bike and you will be amazed on how much of a difference proper sag settings will make. It will take you several laps to adjust to the new feel because you have learned on a tight setup and the looser ride will feel odd at first but take it easy and work back up to speed/lower lap times.

Keep good track notes about tire pressures, shock settings, track temp, outside temp etc...... Most of all have fun, learn the bike and the track speed will come with saddle time.

Keep the rubber side down!!!!!!
 

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Sponge, with that soft rear end you will be squatting too much which will be contributing to your understeer. I cant believe racetech set you up with 46mm of rider sag, that's a soft street figure.
 

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Sponge, with that soft rear end you will be squatting too much which will be contributing to your understeer. I cant believe racetech set you up with 46mm of rider sag, that's a soft street figure.
Agreed. I don't know what my rider sag numbers are like on this bike but my rear end is stiff as ****, just the way I like it! :D I think the free sag is like 4-5 mm. Guessing rider sag no more than 20-25 mm. I've been told by the dad of one of the kids who races in CEV junior class now and Red Bull Rookies cup last year that everyone at that level sets up their bikes really stiff, to where there's almost no free sag at all. I've heard similar things from people who have ridden MotoAmerica bikes (600s or 1000s), that they feel almost unrideable to most of us mortals. Of course I didn't go that crazy with the stiffness of the suspensions on my bike since I'm nowhere near that level, but figured I'd try to stiffen things up a bit more and it seemed to work quite well so far.
 

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I think those fast riders are set up stiff because they are hitting the bumps harder due to faster speeds than mere mortals. Think of the difference in how a modern trials or enduro bike is set up vs something for MX or Supercross.

I saw a comment recently that often the first thing a suspension tuner will do when asked for help is back off the preload and damping a bit from where the rider has jacked them up to, and that often gets an improvement of some sort in lap times right away.

Road racers used to have 60-90mm of travel, and they needed to be stiff to not blow through that immediately. Of course, the damping was pretty rudimentary too so making the suspension immobile to offset the bad dampers that couldn't control much movement was probably common. They often had little or no extension travel available because they were largely topped out all the time, so if they went over a dip the suspension could not extend into it and follow the pavement. The tire needs travel in both directions to stay in contact with the asphalt, it isn't all about only the bump travel.
 

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Discussion Starter #113
Ok so as it turns out, I actually do have a 8kg rear spring. I don't know why the data sheet given to me by racetech has it listed as a 6.3kg. I'm having the front springs replaced, moving to .8kg springs up front. Plan is to try and get 35mm-40mm of loaded sag up front. As for the rear, the sag is at 46mm. Going to change that to 25-30mm, see how the compression and rebound are from there and adjust accordingly. Racetech was adamant that the 46mm rear sag figure is correct, but from all the research I've been doing it just doesn't make sense. I'm going out to chuckwalla on the 13th, hopefully there is a suspension specialist there to help me get properly dialed in. Getting some Pirelli TD's put on the bike as well. Means a 140/70R17 rear tire, should raise the rear just over 1/2" (12.7mm). Hoping all this helps with my understeering issue. Going to have to take it really easy on the 13th to shake off all the cobwebs, as I haven't properly rode at the limit since my crash...
 

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Sounds like a good plan. One conclusion I've come to with suspension settings is that one size does not fit all and you are best to experiment with what you think may work best for you and then tweak from there. For example when I first started racing a fellow racer at the track who had a lot of experience told me to run 5mm of bike sag. My poor old GSXR was fishtailing into every slow corner when hard on the brakes cos I didnt have enough weight on the rear wheel. With my light weight and the lack of bike sag the shock was topping out early and the wheel was losing contact with the track. These days I run about 1/2 an inch of static sag and it's happy days. Oh and I ignore pretty much any suspension advice that guy throws my way! :giggle:
 

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Ok so as it turns out, I actually do have a 8kg rear spring. I don't know why the data sheet given to me by racetech has it listed as a 6.3kg. I'm having the front springs replaced, moving to .8kg springs up front. Plan is to try and get 35mm-40mm of loaded sag up front. As for the rear, the sag is at 46mm. Going to change that to 25-30mm, see how the compression and rebound are from there and adjust accordingly. Racetech was adamant that the 46mm rear sag figure is correct, but from all the research I've been doing it just doesn't make sense. I'm going out to chuckwalla on the 13th, hopefully there is a suspension specialist there to help me get properly dialed in. Getting some Pirelli TD's put on the bike as well. Means a 140/70R17 rear tire, should raise the rear just over 1/2" (12.7mm). Hoping all this helps with my understeering issue. Going to have to take it really easy on the 13th to shake off all the cobwebs, as I haven't properly rode at the limit since my crash...
Jarrad at Motosport Exotica usually brings a trailer to Willow Springs and I think also to Chuckwalla. He did the dyno tune on my N400 and rebuilt my Ohlins on my Ducati. He helped get the bike suspension dialed in and explained everything along the way. Great guy.
 

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Discussion Starter #116
Jarrad at Motosport Exotica usually brings a trailer to Willow Springs and I think also to Chuckwalla. He did the dyno tune on my N400 and rebuilt my Ohlins on my Ducati. He helped get the bike suspension dialed in and explained everything along the way. Great guy.
He tuned my 400 too. Motorsport Exotica is a great business, all the guys there are great too.
 

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Ok so as it turns out, I actually do have a 8kg rear spring. I don't know why the data sheet given to me by racetech has it listed as a 6.3kg. I'm having the front springs replaced, moving to .8kg springs up front. Plan is to try and get 35mm-40mm of loaded sag up front. As for the rear, the sag is at 46mm. Going to change that to 25-30mm, see how the compression and rebound are from there and adjust accordingly. Racetech was adamant that the 46mm rear sag figure is correct, but from all the research I've been doing it just doesn't make sense. I'm going out to chuckwalla on the 13th, hopefully there is a suspension specialist there to help me get properly dialed in. Getting some Pirelli TD's put on the bike as well. Means a 140/70R17 rear tire, should raise the rear just over 1/2" (12.7mm). Hoping all this helps with my understeering issue. Going to have to take it really easy on the 13th to shake off all the cobwebs, as I haven't properly rode at the limit since my crash...
It all sounds good except the front, I'd set it up no more than 35mm of sag or you may bottom out under braking. I just put a set of TD's on for my last time out and these things STICK!!! Almost too well, after a lap or two I picked up the pace and found myself lifting in turns that I am used to sliding in so now I'll get to push harder to find the slide. I am running the 110/140 combo too but I have been from the start. I also have raised the rear 3/4" from stock and lowered the front 5mm from stock.
I found that the tires are ready to go before completing the first lap from cold. They do not stick as well as a slick but don't require tire warmers so that is why I am on these currently. I will know more after this weekend on my home track.
 

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Discussion Starter #118
It all sounds good except the front, I'd set it up no more than 35mm of sag or you may bottom out under braking. I just put a set of TD's on for my last time out and these things STICK!!! Almost too well, after a lap or two I picked up the pace and found myself lifting in turns that I am used to sliding in so now I'll get to push harder to find the slide. I am running the 110/140 combo too but I have been from the start. I also have raised the rear 3/4" from stock and lowered the front 5mm from stock.
I found that the tires are ready to go before completing the first lap from cold. They do not stick as well as a slick but don't require tire warmers so that is why I am on these currently. I will know more after this weekend on my home track.
I'm at 31mm loaded sag on the front and 30mm on the rear now. Rear end feels way stiffer. I haven't messed with damping or compression yet, just going to take it easy next Sunday at the track and slowly start dialing it in hopefully. I took it around the block with the TDs, the soft carcass compared to dunlop is nice. You can feel more of what the tire is doing.
 

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Discussion Starter #119


So after much research. Manic Moto changed the front springs to .8 kg and we adjusted the race sag of the rear shock to 30mm. They flushed all fluids and installed a set of pirelli TD's, checked head bearing torque, replaced the chain. Headed out to chuckwalla Sept 13th for socaltrackdays. They run a no sessions format, so the track is just open and you can go out and pit as much as you please. Chuckwalla had repaved the entire track 72 hours before we went out. The amount of debris was insane, was told to treat the day like the track was wet... every bodies belly pan was basically full of the stuff by the end of the day and we had 5 red flags. Also ruined the paint on the front of my belly pan...





I ran 32 PSI front and 25 PSI rear COLD per Pirelli's recommendation sheet and never needed to adjust pressures all day. Tire wear was perfect. Way more feel, heat up faster, and way more grip than Q3+.





The racing line had good grip but anything off of it was slippery as ****. Learned a lot about riding with limited grip and the day was an overall success. The bike feels better than it ever has. No more understeer and way more responsive when leaned over. My Mithos leathers are comfortable and don't restrict me at all, really happy with my purchase. First race is on the 26th of this month, I'm hoping track conditions are going to be a lot better.





Only excitement I had all day is when some guy stuffed me, which I found very rude during a track day. Luckily I kept my cool, followed him for a couple laps and then passed him on the outside of the same turn he tried to get me to asspack him in.

imgur album
 

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That's an insane amount of stones. Hate to think of the shrapnel you'd get following other bikes.
You know things are bad when you need an oversize drainage hole on a dry track day.
Loved your overtake of the cocky dude.
 
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