Suspension on Used Track Bike

[faintlypinkflower]

I recently picked up a used 2018 Ninja 400 and I just had a question about when/if you get a bike resprung for your weight.

The bike was sprung for a 190lb. person and I'm 150lbs. It has a Andreani Misano Fork Cartridge Kit and a Penske rear shock. I'm not sure what springs are in there now though.

I know this question has probably been asked before and when I was trying to research this on my own, it seems like when you are first starting out, don't worry about all this until you get faster. I also assume the best bet is to find a trackside suspension person to help set up SAG?

I'm trying to get this bike ready over the off season, so I wasn't sure if this was something I needed to worry about or just clear it out of my mind and stop overthinking it. Haha. I know this bike is overkill for my current level but I figure I'll grow into it as I keep practicing. I've only done one track day so there is so much to learn.

Thanks so much!

 

[bmart]

Welcome to a great sport and group, Emily!

You're right about being curious, and also about suggesting that it is adequate as it is at this stage in your development.

It may be worth checking the rate on the springs and comparing those to what would be correct for your weight. Most springs have writing on them. Many folks are likely willing to help you if you aren't able (or dont' want to) do it yourself. An easier way would be to ask the previous owner, who may have recollection or a receipt for the work done.

If you do decide to do it now/later, on this bike or another, the valving may need to be modified to match the alternate spring action. There are a lot of great suspension places out there. Some may be near you, but there's nearly always one at a track event who is there to help.

You can check sag on your own, preferably with the chassis warm (after riding it). You can do it with a ruler and a friend who can reliably read a ruler (harder than you might think these days!) or using one of my favorite tools call a Slacker. General street bike guidelines (definitely better when you're starting out) are:

Front bike-only sag 20-24mm, rider sag 35mm
Rear bike-only sag 8-10mm, rider sag 30mm

You can tell if springs are too soft or hard from your sag numbers compared to these numbers. Know that these are not set in stone and that riders, as they get faster, have preferences for softer or harder springs.

There are systems, maintenance, adjustments worth looking at/changing in the off season. Post up if you want more info about those in addition to the boingers.

What else do you know about the bike?

And as always, if you get down south, come by and say hello!

 

[PatricksDad]

If you have the budget to use a shop to get you baselined, MRP Motorsports in Pasadena can help, and they could be less than 30 minutes from you depending on where in Columbia you are.

 

[faintlypinkflower]

Welcome to a great sport and group, Emily!

You're right about being curious, and also about suggesting that it is adequate as it is at this stage in your development.

It may be worth checking the rate on the springs and comparing those to what would be correct for your weight. Most springs have writing on them. Many folks are likely willing to help you if you aren't able (or dont' want to) do it yourself. An easier way would be to ask the previous owner, who may have recollection or a receipt for the work done.

If you do decide to do it now/later, on this bike or another, the valving may need to be modified to match the alternate spring action. There are a lot of great suspension places out there. Some may be near you, but there's nearly always one at a track event who is there to help.

You can check sag on your own, preferably with the chassis warm (after riding it). You can do it with a ruler and a friend who can reliably read a ruler (harder than you might think these days!) or using one of my favorite tools call a Slacker. General street bike guidelines (definitely better when you're starting out) are:

Front bike-only sag 20-24mm, rider sag 35mm
Rear bike-only sag 8-10mm, rider sag 30mm

You can tell if springs are too soft or hard from your sag numbers compared to these numbers. Know that these are not set in stone and that riders, as they get faster, have preferences for softer or harder springs.

There are systems, maintenance, adjustments worth looking at/changing in the off season. Post up if you want more info about those in addition to the boingers.

What else do you know about the bike?

And as always, if you get down south, come by and say hello!

Hi! Thanks so much for this thorough response!

So I asked the previous owner, and he didn't know the spring rate of the suspension. They were in there when he got it and then a shop trackside set it up for his weight (190). Thanks for providing those sag numbers.

I've always tried to do as much maintenance as I'm able to do myself because a) it's a hobby in itself and b) it's a fun learning process. I wasn't sure if replacing springs or like suspension work was something people do themselves or like you go to a shop for.

The bike still needs a bit of work before it can see the track like new brake pads, front rotor, safety wiring and stuff like that. The speedometer doesn't work because of an abs delete but I've heard you shouldn't be looking at that anyway. It's set up for gp shift but I've been reading horror stories of people downshifting instead of upshifting and crashing so I might change it back. I'm just trying to go down the list and think of everything I can do ahead of time to get the bike in a better working order.

It's not street legal, so unfortunately the first time I'll be trying the bike out will be on the track. Which brings me to another point, I know track bikes are a special case because you can't ride them on the street but it's already been an interesting experience because it's like a whole new way of looking at things as in owning a street bike vs a track bike.

As far as systems, maintenance, adjustments worth looking at/changing in the off season, I'll take any info I can get as I'm just making sure I don't forget anything. Thanks so much!

I was up at NJMP last weekend but next year I would like to make it down to NC and if I do I will certainly come say hi. Everybody at my first track day was so welcoming and open with sharing their knowledge, it was a great experience.

 

[faintlypinkflower]

If you have the budget to use a shop to get you baselined, MRP Motorsports in Pasadena can help, and they could be less than 30 minutes from you depending on where in Columbia you are.

Yeah that's not far at all! This is really helpful. Thanks so much!

 

[HondaGalToo]

Hi Emily! Great questions! I second the advice to take it to MRP. They can swap the spring and do a baseline setting. I like doing as much work as I can on my bikes as well, but I leave the suspension to the experts. I'm not positive, but I think special tools are needed to compress the fork to swap springs. But, also encourage you to learn to do it! That should be the next thing I learn more about - suspension.

 

[PatricksDad]

If you can make the sag numbers above work with the existing springs, you’ll be fine. Spring rate is really more a question of pace, generally, than weight. A 140 expert might be good with the same spring my 190 lb beginner ass needs.

I’d say your priorities should be safe, then building consistency through skills development. Until you can be comfortable and consistent, you won’t necessarily know what effect any changes will have. Laps and coaching are the only investment you need now.

However, learning your bike by doing maintenance and repairs within your skill set is never going to be a bad thing. Enjoy the journey.

 

[faintlypinkflower]

Hi Emily! Great questions! I second the advice to take it to MRP. They can swap the spring and do a baseline setting. I like doing as much work as I can on my bikes as well, but I leave the suspension to the experts. I'm not positive, but I think special tools are needed to compress the fork to swap springs. But, also encourage you to learn to do it! That should be the next thing I learn more about - suspension.

Hi Judy!

You feel so good after doing work yourself! And I think you might be right about the special tools. Oh! So in looking up suspension, people on reddit recommended this book (linky) and I'm not sure if it is good but it might be fun winter reading. ¯\_(ツ)_/¯

I think I might try to also attempt a norton motorsport clutch upgrade which would be my most adventurous thing I've tried doing myself.

 

[faintlypinkflower]

If you can make the sag numbers above work with the existing springs, you’ll be fine. Spring rate is really more a question of pace, generally, than weight. A 140 expert might be good with the same spring my 190 lb beginner ass needs.

I’d say your priorities should be safe, then building consistency through skills development. Until you can be comfortable and consistent, you won’t necessarily know what effect any changes will have. Laps and coaching are the only investment you need now.

However, learning your bike by doing maintenance and repairs within your skill set is never going to be a bad thing. Enjoy the journey.

This all makes sense and has been what I've been finding in my limited research. I really agree with all of this. Thank you!

 

[Menotomy]

I'll third the recommendation to take it to MRP. Since you mentioned it was used, in addition to swapping springs if necessary, they can refresh the fork oil and replace seals, re-valve it, make sure the forks are straight and straighten them back to spec if needed. Same with the shock. Personally I have MRP do all my suspension and motor work, but everything else I do myself in my garage (including fiberglass repair, ugh).

It definitely doesn't hurt to read about suspension tuning in the offseason. The book you linked is popular, and YouTube will have some good videos if you're more of a visual learner. If you decide to start maintaining suspension yourself you at least know you havea good baseline after having MRP look at it.

 

[faintlypinkflower]

I'll third the recommendation to take it to MRP. Since you mentioned it was used, in addition to swapping springs if necessary, they can refresh the fork oil and replace seals, re-valve it, make sure the forks are straight and straighten them back to spec if needed. Same with the shock. Personally I have MRP do all my suspension and motor work, but everything else I do myself in my garage (including fiberglass repair, ugh).

It definitely doesn't hurt to read about suspension tuning in the offseason. The book you linked is popular, and YouTube will have some good videos if you're more of a visual learner. If you decide to start maintaining suspension yourself you at least know you havea good baseline after having MRP look at it.

I would feel better about having a baseline and then being able to work from that. It should be money well spent. Also good to have somebody else look over the bike because another set of eyes is always a good thing. Thanks!

 

[bmart]

Hi! Thanks so much for this thorough response!

So I asked the previous owner, and he didn't know the spring rate of the suspension. They were in there when he got it and then a shop trackside set it up for his weight (190). Thanks for providing those sag numbers.

I've always tried to do as much maintenance as I'm able to do myself because a) it's a hobby in itself and b) it's a fun learning process. I wasn't sure if replacing springs or like suspension work was something people do themselves or like you go to a shop for.

The bike still needs a bit of work before it can see the track like new brake pads, front rotor, safety wiring and stuff like that. The speedometer doesn't work because of an abs delete but I've heard you shouldn't be looking at that anyway. It's set up for gp shift but I've been reading horror stories of people downshifting instead of upshifting and crashing so I might change it back. I'm just trying to go down the list and think of everything I can do ahead of time to get the bike in a better working order.

It's not street legal, so unfortunately the first time I'll be trying the bike out will be on the track. Which brings me to another point, I know track bikes are a special case because you can't ride them on the street but it's already been an interesting experience because it's like a whole new way of looking at things as in owning a street bike vs a track bike.

As far as systems, maintenance, adjustments worth looking at/changing in the off season, I'll take any info I can get as I'm just making sure I don't forget anything. Thanks so much!

I was up at NJMP last weekend but next year I would like to make it down to NC and if I do I will certainly come say hi. Everybody at my first track day was so welcoming and open with sharing their knowledge, it was a great experience.

Emily,

If you are able (competent and thorough), doing the work yourself can be very fulfilling...and allow you to make fixes at the track when you need to, saving you time/money.

GP shift is a personal thing. I never wanted to go back and forth from my street bikes, so I left my track bikes in the mor orthodox one down configuration. I've also never had the need for changing it due to rubbing my toes on the ground while trying to shift at extreme lean angles.

Regarding going through the bike in preparation, I like to make my list by systems and then slide tasks into the right order to make it easy on myself. I'm lazy and hate to repeat work (like installing brakes, then having to remove them again to work on a later task). Maybe ergonomics/controls, braking, drive, electronics, engine...something like that. I'd start by removing bodywork for anything that it needs and leaving it off until everything else is completed and checked for good working order. Clean everything which will make it more enjoyable to work on. Then up on stands, wheels off, tank up/off, and dive in! I'm happy to help through the forum, as I am sure that many others are too. you may get conflicting info, but there's usually more than one way to skin a cat, as they say. Folks will have their preferences for oil/chains/tires, sag #s/etc. Any answer from an experienced rider should get you in the ballpark.

One can make this a very expensive or a relatively inexpensive sport, and I'm not sure that spending more money makes it better, safer, or more enjoyable, so choose your poison. I'm not sure that anyone runs any cheaper than I do. The best money is spent on quality safety gear (new/used), training, and seat time. And you can learn a lot from the coaches on track, online, and in the paddock...and we're free. (Last weekend my the end of my season and it was really great that quite a few riders from the weekend and the last year or two came up to thank me and other CRs for all of the help we've provided and commented and how much faster and safer they rode now. That's a great feeling for both of us!)

 

[The B Team]

I've always tried to do as much maintenance as I'm able to do myself because a) it's a hobby in itself and b) it's a fun learning process. I wasn't sure if replacing springs or like suspension work was something people do themselves or like you go to a shop for.

The bike still needs a bit of work before it can see the track like new brake pads, front rotor, safety wiring and stuff like that. The speedometer doesn't work because of an abs delete but I've heard you shouldn't be looking at that anyway. It's set up for gp shift but I've been reading horror stories of people downshifting instead of upshifting and crashing so I might change it back. I'm just trying to go down the list and think of everything I can do ahead of time to get the bike in a better working order.

It's not street legal, so unfortunately the first time I'll be trying the bike out will be on the track. Which brings me to another point, I know track bikes are a special case because you can't ride them on the street but it's already been an interesting experience because it's like a whole new way of looking at things as in owning a street bike vs a track bike.

As far as systems, maintenance, adjustments worth looking at/changing in the off season, I'll take any info I can get as I'm just making sure I don't forget anything. Thanks so much!

I was up at NJMP last weekend but next year I would like to make it down to NC and if I do I will certainly come say hi. Everybody at my first track day was so welcoming and open with sharing their knowledge, it was a great experience.

Some thoughts on this. If MRP is close and you just want a baseline, have at it. If you are going to regularly be participating at N2 events and want to build a relationship with someone that is going to be trackside to help you, then I would recommend Pitlane or Bobblehead. They are initially quite far for you, but will be the ones you'll see at every TD when you get there. Coincidentally in the case of Pitlane, this will also be the guy selling you parts when you're in a pickle, and has the pads/rotors/etc you mentioned.

Special tools are required to change springs out, replace seals, and set fluid levels, but they're easy enough to come by. Valving and whatnot is much more expensive and best left to the professionals.

Safety wiring isn't needed at novice pace, but we all have to find something to keep away the twitch of the offseason, so have at it. Might as well ditch the coolant while you're at it, if you have a heated garage, or at least drain and flush it in prep to refill in the spring.

Buy the elite membership.

Have a killer offseason, see you at the track.

 

[The B Team]

Also meant to say to your bit about street legal...400s are in the realm of kart track and minimoto, and you can always trailer to an abandoned parking lot to practice.

 

[faintlypinkflower]

Some thoughts on this. If MRP is close and you just want a baseline, have at it. If you are going to regularly be participating at N2 events and want to build a relationship with someone that is going to be trackside to help you, then I would recommend Pitlane or Bobblehead. They are initially quite far for you, but will be the ones you'll see at every TD when you get there. Coincidentally in the case of Pitlane, this will also be the guy selling you parts when you're in a pickle, and has the pads/rotors/etc you mentioned.

Special tools are required to change springs out, replace seals, and set fluid levels, but they're easy enough to come by. Valving and whatnot is much more expensive and best left to the professionals.

Safety wiring isn't needed at novice pace, but we all have to find something to keep away the twitch of the offseason, so have at it. Might as well ditch the coolant while you're at it, if you have a heated garage, or at least drain and flush it in prep to refill in the spring.

Buy the elite membership.

Have a killer offseason, see you at the track.

I know how invaluable it can be to build that relationship and this is great advice to get a head start on that. I would normally do this but unfortunately, I'll be moving sometime mid next year to SoCal. I plan to jump on events in the beginning of the year and hopefully I'll have time to do a fair amount before the move.

It is a bummer there are many great tracks on the east coast and I've really felt so welcome by everybody at N2 so I will miss all of that. I'm sure the track scene in cali is about the same-ish... maybe

See you at the track! Also thank you for all your advice!