I was going to wait a little longer before I posted anything but here it is anyway. Some of you are going to ask, "Why?" My bike & i go way back! I love the powerband of the 919, & its got less than 10K on it. The changes I'm making to the bike are just as fun riding the thing. My biggest complaint of the stock bike was the rake, soft springs and the boring look of the front end. The project started about a year ago but ive been away from home for over 300 days on 2009 (so far.) that being said, I'm hoping to have the bike done by the end of January but a may need to leave again.

before,


& After (sort of, not done yet...)


The fuel pump has been changed out for a walbro __?__, I cant remember the model number, I'm hoping it doesn't draw too much power. The front end is being switched over to 07' 1000RR forks w/ 320mm rotors but I'm waiting for 1 last part to come back from machining. The swing arm/rear shock are from an 08 (i think) 600RR. I haven't even started on it yet. I plan to have it bolted up tomorrow minus the shock & linkage. the Seat is carbon fiber/kevlar, self supported but still needs some work. tail is shark skins from an 1125, it too needs some more more. GT1548, looking for 100ft/lbs w/o an intercooler which is 46% over stock. At this point, I have no idea how im going to put an intercooler on there.


I still need a headlight but I just cant figure out what to use. Anyone have any thoughts?

 

I don't think you will need an intercooler. Who is making your manifold and airbox?

For headlights, I really like the buell twin headlight setup. I think it's from the XB9

 

Fun winter project (or year-long if you're away so much).

Have you checked the spring rate on the 600RR shock? Might be a touch too light for the heavier 919 motor and frame.

What steering head bearings will you be using? Might be worth it to upgrade to some tapered bearings.

 

I have not checked the spring rate. I got a 08' shock for $40 shipped from the states, they go for about $75+ here in the UK so worst case, I can sell it. Ive ditched a lot of weight so far. i'm thinking perhaps as much as 20 pounds when i'm done. still heavier than the 600RR. Where can i find tapered bearings? right now im planning on just using the 919 bearings. would i see a diff from the tapered?

 

Im getting the turbo as a kit from a guy in CO. airbox is CNC it will be set to run at 7PSI on the GT15 but fuel becomes an issue as the duty cycle on the stock injectors reach their limitations. I have a different fuel pump & a wideband; stock fuel pressure is 50psi so hopefully i can crank up the fuel pressure a little and get a better duty cycle.

I'm trying to avoid spending a fortune on this project. Though it may look like im dumping tones of $$$$ in to it, ive actually got amazing deals on most of the parts mainly from ebay. A few items like my rear sets were shipped from japan. I got the tail for $50 -new.

 

Get tapered bearings from All ***** Bearings. They are smoother and last longer.

 

i would definitely try to find the wheel rate of the 600rr suspension and then see what it's going to be like when you've mounted everything up. it looks like you may be changing a lot of the geometry out back, so you'll want to make sure that do don't end up with something way too soft or way too hard.

 

how/where can i get more info on this? my first concern was really just getting things bolted up. i figured i worry about the spring rate after I got the swing arm on.

 

the easiest way is to just measure it directly, although you can't exactly measure it on a 600rr right now. basically just bolt everything up with the spring off the shock. then move the wheel a certain amount and see how far the shock shaft moves. that will give a rough estimate, although to be absolutely sure you'd want to measure it in a few different angles of the swing arm because you may not have a constant motion ratio between the wheel and the shock.

although if you're never really going to push the suspension all that hard, doing it how you currently plan on doing it might be good enough.

 

I see what you mean. from what it looks like, there is no way in hell that ill be able to use the stock shock mount. There will prob be some welding and fab. If poss, ill try and make the mounts in a way that uses the length of the shock i have. I didn't get the swing arm mounted today. i need to cut the frame, the black pieces that the rear set connect to & the swing arm to mount everything up. I started one of the small cuts and my Dremel died after about 60sec. I think its dead for good & not just brushes. oh well. If I'm not too hung over tomorrow, I'm hoping to finish it up. Ill post some pics when it mounted.

 

she is not for sale but for the right price, you can have her...

In other news, the swing arm is on!!! now that it is, I have found another problem. the frame which has already been cut has to supports which you can see in the 2nd picture. The swing arm isn't going to work unless I remove them so my plan is to cut them off and work from there. since there is no room for a passenger to sit (frame was cut) I think i may be able to go without the supports. when everything is done, if it looks like there is too much flex ill add a brace in. I have a lot more carbon & Kevlar so maybe ill use that.

 

braces cut, still need to clean up the metal around the end of the tail

 

You're definitely going to need to brace the seat area. FWIW, the RC51's subframe bolts to the main frame. Maybe you can adapt that style of subframe to your bike by welding mounting tabs.

I really dig a swingarm on that chassis. I think it's going to look **** if you can get the shock to work.

 

FYI the frame is chrome-moly. does that change your thoughts on the braces?

 

cool project man.

we have a few guys with turbo builds, and tons of people with experiance in swingarm/frontend swaps so if you have any questions check out customfighters.com

ive given you my opinions on headlights not to long ago, but theres plenty of options out there. the 1000rr forks are a good pick, i like using them or 929/rc51 frontends. try to get the all ***** bearings, ive used them in my old gsxr 750 and they are quality. and for the swinger, i would of went for a vfr sssa just because i think the fitment is lot easier and a hair longer cause your going to need a long swingarm with the power of a turbo, lol. i believe the 07 600rr swingarm is even shorter then the 06 and back so you may want to reconsider that.

from the top of my head, theres 3 guys building turbo bikes with lots of knowledge on there so they could possibly help if you have questions. two are building turbo gsxr 1100s, and one is building a turbo ninja 250.

as for the subframe, i would cut it off completely and have new tabs welded to the frame. then build an aluminum subframe and use heim joints so you can adjust the height.

 

no. I think it'll still need to be braced. I'm no engineer but unsupported, I'm pretty sure it will fail which will lead to a big o'****

 

I originally looked at the RC51 forks but decided against it because the length. RC51 are the same length as the stock 919 which has a boring rake. the 1000RR are quite a bit shorter.

you make a good point with the swing arm but the last thing i want is a stretched bike. Im using a GT1548 so it spools up quick. my plan is to "attempt" a track day at least once. we'll see what the spool up has to say about that one... the 600RR swingarm is actually slightly longer than the stock 919. I don't know the exact number but i would say about 1cm.

I really like you idea with the hacking off the rest of the frame. It would be really nice to use a subframe from another bike already welded up. I dont have access to a TIG welder and im living in the UK right now getting paid in USD so I would prefer to not ***** out the work.

 

You may need different offset triples to fix your trail if the forks are shorter

 

are you looking to do a real track day or a day at the drag strip?

for the swingarm, the vfr swingarm cant be more than an inch longer than the 919 or 600rr. but if your in england and you want to do this as cheap as possible go with the route you think is best. all i know is your front wheel is going to be in the air all the time with a turbo strapped to it.

i dont know what part of england your in but theres tons of bike builders and its the birthplace of streetfighters so theres alot of people you could get connected with for help, advice, and anything of the sort.

i didnt even realize the frame was chromoly, i forgot about that. id use the existing subframe then for the tail. its a whole lot cheaper and easier to weld that then aluminum.

 

I'm not the first to do the swap. A friend of mine did this a couple years ago with no problems.

 

I've never seen someone try and use a 600RR rear swingarm. Good luck with that. It'll be different. But with the tq and power of the turbo motor, you'll in the air. Especially with a tight wheel base.

919 doesn't have much ground clearance so as far as track days, glad your getting rear sets. I've did track days with the stock stuff and was scraping quite a bit. Not too mention it's taken me down a couple times...

I shall enjoy the updates as I'm a fellow 919'er.

 

I didn't mean it wouldn't work, but shorter forks are going to reduce your rake angle, which will change your trail, thus changing the way the bike handles. Combine that with the shorter wheelbase from the RR swingarm, and it will be noticeable.

I think the 919 has 35mm offset triples, and the '06 1000rr has 25mm offset. I don't know how much shorter the RR forks are, but they will reduce your rake angle. Basically, if you use the RR triples, you will need a 22.5degree rake angle to keep the same trail (the stock is 25degrees for the 919). Once you get the suspension bolted up, I would measure everything and see what you need to adjust to set the trail where you want it for best handling. If the rear sits higher from the new swingarm setup, you will further lower the rake angle giving even shorter trail. Too little trail = instability.

 

Sweet project man. Hoping to see some nice power from the bike when it's done. 919 fo life!

 

I got my shock in, I placed in in the swing arm with the equalizer and pushed bolts through. this is the beginning of the messy part. Im going to need to weld on tabs or/and extend the frame for a bolton point to the connecting rod. Before I do this would like to understand exactly what pro link is. I'm having a little trouble understanding unit pro link. I found a 30 page article on unit pro link with engineering specs but its mid night and i need to be up at 6am. Thought someone would be interested

http://www.atnet.it/lista/casuni.htm

 

I should have been home by now but United canceled my flight and wont have another flight for 3 days. on top of that they lost my baggage. I have my laptop, my toothbrush, some snow boarding goggles & thats about it... stuck at a hotel in Chicago ive been spending a lot of time working with Linkage V2.5 which was recommended to my by another HT member (ill post his/her name later.) What I've found is that my project is expanding more and more but im loving ever min of it! It kills me because I only wish I would have had some direction in all this when I was younger. I had to pay a little for the software but it was worth every cent. does anyone know the spring rate of the 600RR rear shock? how can i measure this?

the picture below is very rough because i don't have the bike in front of me to take measurements off of but the general idea is there. When I get home if i ever make it, ill input the correct numbers and repost the results.