1988 VTR250

This is the 7th VTR250 I have owned, but the last one was back in like 1996 so it's been awhile since I tinkered with one of these.

Picked this one up for a smokin price in decent cosmetic condition, but running on just one cylinder. I figure I could have sold the aftermarket middle fairings & the Hondaline Solo Seat cowl for almost as much as I paid for the whole bike so if I couldn't get it running properly I wasn't going to be out much in the way of dollars which is good as money is more than a little tight currently...

Many thanks to those that have offered parts & services for this project!!!

 

1988 VTR250 Gearing Spreadsheet (Excel)

1989-90 VTR250 Gearing Spreadsheet (Excel)

Mods List

Stage II Jet kit with truly custom jets & needles as the ones supplied in the kit didn't get
the A/F ratio I needed throughout the entire rev range

Sato Racing Titanium MotoGP cannister

ProGrip 717 Grips

Kyle Racing Stainless Steel Bar Ends

1000RR Nissin Radial Master Cylinder with CRG Lever

Spiegler custom Brake line (white with Ti fittings)

EBC Race Pads (I usually abhor anything EBC, but aftermarket parts for a 22 year old
bike are hard to come by...)

DID ERV3 520 Chain

AFAM 46T Rear Sprocket

PBI 14T Countershaft Sprocket

Honda Elite Mirrors made by some Taiwan knock-off company

JDM Flushmount front turn signals (not installed yet)

Super fat Dunlop K505 140/70/17 Rear Tire

Progressive Fork Springs (that's all I could find that would fit...)

Custom Ohlins Shock to test fit had to go with the Ti spring!

 

 

Started stripping it down & giving it some love; new battery, spark plugs and some serious bead blasting to various parts to make
them look new again as best I could and then powdercoated the parts that required it.

Also removed all unnecessary brackets, bolts & passenger pegs plus the EVAP system
shedding more than 10lbs off this already very light streetbike

Who knows how long fuel had been dripping on the valve covers...

Before

After

 

 

Quite a few people have asked about the front brake...

It is a vented cast iron disk INSIDE the wheel housing

 

 

 

First reassembly

 

Very Special thanks to Sato Racing for supplying me with this
Titanium GP style silencer

(I'll be working up a proper mount for it soon)

Dyed the Seat Black

Installed the Honda Elite (knock-off) Mirrors

 

YES you can shoehorn a 140-70-17 Dunlop K505 on a 2.5" rear rim!

I used to do this back in the day with the K591R & later the SP tires, but they have long since been discontinued.

Best I can tell these new Dunlop K505's are the exact same bias ply
carcass as the old K591's they just have a different (updated) tread profile.

Basically what you get out of this is 3 things:

1. A super phat tire that makes the bike look way bigger from behind than it actually is :)
 
2. A much needed taller rear ride height to alter the bike geometry & get some weight on the front end
 
3. WAY More tire than you can use... You will drag hard parts before you run out of tire!

 

 

By the way when you are working on the carbs there is no better place to set the tank than an unused tire
It protects the petcock & the tank perfectly

 

There has been a lot of talk about proper carb jetting, but let me tell you this. In 20+ years of jetting bikes and owning 7 of these VTR250's not once have I been able to get the Stage II Dynojet kit to work properly without sacrificing drivability. Sure you can swiss cheese the airbox and make it run pretty good on top end, but then the low & mid-range suffer terribly. If you tune it so that the mid-range is decent then you get a turbulence induced stumble on the top end that in my opinion gets even worse with a high flow (K&N type filter)

Basically I can get the bike to run good on the dyno, but in the real world I get a lot more air into the airbox that causes the bike to run rough on top end so what I have done is split the difference & I use a more moderate jetting with a lightly modified airbox.

I remove the entire rubber snorkel (which weighs damn near as much as the airbox lid itself) & I drill eight 1/2" holes in the airbox & chamfer the edges and I have learned to stick with the OEM air filter for many reasons. Most of which I explain in this article here if you are so inclined to read it.

 

 

Still to come will be the tank painted black & I scored some OEM Japanese Spec flushmounts that mount in the upper fairing like this:

 

Still haven't installed the flushmounts, but the got the fuel tank & middle fairings resprayed