Sprint RS....New beginnings

Hi folks, just recently acquired a very sorry RS. Having sold my road bike of 10 years, a GSXR7/12 which evolved into a seriously capable bike, to go drag racing, the time had come to get back out on the roads.
I was in a period of looking for something different having owned a stream of gsxr's and the like when the RS came along, after the first ride i knew i was gonna like this bike......

On to the bike.... When i got it every body panel just about, was broken. Scouring ebay resolved all but the headlamp fairing so far. Also a pipewerks race can for a 1050 sprint was acquired for under £70. The 1050 has a single sider and the exhaust headers exit at a different point. Ebay again has turned up a pre bent 45 degree polished stainless tube which should marry the 2 parts up nicely. Once the exhaust is sorted, next step will be giving the motor a service followed by a dyno session to check fuelling. Then will be looking at some suspension upgrades

Steve

 

Yes mate, engine and box seem fine although a bit flat up top end, but hopefully service will cure that once i get time

 

Today saw the release of the 3 cylinder growl......
Having acquired a pipewerx can for a 1050 very cheap brand new from ebay, the link pipe was too short and the wrong angle. My ordered polished 45 degree bend turned up during the week, offered it up this morning and bingo. 10 Mins with a disc cutter and TIG welder, i nicked the end off of the original pipe and welded it in, cut the slots for clamping, made a small spacer to sit the can out so it cleared the caliper and arm, 1 longer bolt and jobs a good un, sounds spot on. Brand new end can that fits for under £100 all in :upyeah:

This actually applies to any 2" slip on can, the bends can be bought from ebay in polished stainless for under £15 and even if you dont have the tools or capability to do it yourself, any friendly engineering shop should be able to sort you for around an hours labour :upyeah:

Will put some pics up later
Steve

 

If you want to do thid mod, heres the bend i bought
Stainless Steel Polished Elbow Pipe Bend Exhaust Pipework Mandrel Degree Tubing | eBay
57mm 45 degree 150mm
Steve

 

If you want to do this mod the bend i bought was
57mm 45 degree 150mm long
Stainless Steel Polished Elbow Pipe Bend Exhaust Pipework Mandrel Degree Tubing | eBay

Steve

 

Hi Steve
Motads have generally always been "No rejetting required", so you should be ok on that front

Will be looking at re shimming mine very soon, will take all the shims out regardless for making up a spreadsheet, so next time a quick reference and i can have all the necessary shims before i start. Hopefully with that done it should unlock some top end power, but think I'll be doing a compression test and leak down test while I'm at it.

Seen some cylinder heads on ebay going real cheap, might be tempted to buy one and get it flowed and ported, should help free up a few extra ponies, would like to get her up to 150BHP and as near as 100lb/ft of torque as possible, so will also be looking at alternative pistons and cam regrinds....OR.... reckon a garrett gt28rs turbo would work really well on a triple

Has anyone ever ran one of these engines without the balance shaft? That would free up a few ponies too if the vibration was bearable....

Steve

 

After a little adventure last weekend where the bike tried to throw me off over the rough stuff, with the front tucking up on me, suspension is now top of the list. Spent Sunday evening playing with suspension adjustments, no real improvement was made so now waiting to hear back from maxtons.
Seems pre 04 sprints there's very little that can be done with the front, so tailor made revalve and respring looks like order of the day. Unless of course you want USD's up front then swapping out with any one of a number of suzukis. As it goes, i want to keep a RWU front end in it so revalve looks like best option.

After a week of thrashing about, the cam chain is now slapping like a good un. Done some research on this and seems manual tensioners for the oil coiled gsxr's fit most triumphs. Once we have the mill set up we will have as many of these as we want so these will be available to the general public in the next few months.

I will be swapping one off my gsxr race bike tomorrow for now, meanwhile i will be out playing on a 750m streetfighter that came up at "the right price". This will give me chance to get those valves reshimmed .......

Another thing i came across, talking to a friend who has a Speed Triple 955, his was very tame up the top end. Took it to a Triumph dealer who loaded a new map and problem solved.... So guess will have to go and have a word with mr triumph dealer very soon.

Once I get it behaving how it should, then some serious playing can begin.

Steve

 

Reminds me of one or two jap fours I've previously owned :/

 

With the day getting off to a poor start, finally got down the workshop this afternoon. As the bike has been stood a few days, first up was valve clearances. Exhaust were all ok (0.17 ish), intake were all under 0.05!! Probably explain the lack of top end perfformance then. Seeing as all 6 needed doing, i decided to drop the inlet cam. Luckily, all are 2.45 or above so can get 2.3's to go in.

Also decided to check the cam chain tensioner at this point, and sure enough thats worn away 2 teeth so time for a manual tensioner.

Usefull tip to self, when using tip tools, cover plug holes while working on engine!! Yup, the torx bit fell out and straight down plug hole when slackening the cam caps!!
Just one of those days i guess.....

The oil in the head area smells really burnt, and seems pretty thick so guess some previous owner has been using car oil in there, so looks like a flush with some cheap semi coming up before putting fully synthetic in....
So another week to get tensioner and shims, then time her back up once torx bit removed, and get her back together. Be interesting to see what the difference is

Steve

 

May end up giving that a try

 

Quick Update....

Yesterday, double checked shim measurements and obtained new shims from local triumph dealer, well, localish anyway.......

Called in to Grumpy1260s' for a cam chain tensioner then off to workshop to crack on.
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Fitted shims into their respective buckets, oiled cam bearings and shims and set about installing inlet cam. Checked procedure for setting cam timing, looks easy enough..... HA!!!!
Having done cam timing on who knows how many double and single overhead cam 4's, this was a complete t**t to do! Keeping all of that cam chain slack in one place and keeping it taut on front run is a nightmare, cam chain is miles too long on these, anyway, enlisted another pair of hands and got the job done. Ended up putting the tensioner in to get a part tension then timed it up :wink:

The tensioner itself turned into a bit of an episode. Someone had said that the GSXR oil cooled tensioner was a straight swap, well if thats straight then drag racing uses an oval circuit!! As it goes, it does fit, BUT, the opening into the block has castings squaring the round hole off. The gixer tensioner was filed down on 2 flanks untill it resembled the shape of the triumph one. It now went into the hole but wouldn't seat properly, A 7mm drill bit cured that, new gasket, bit of hylomar, and jobs a good un :upyeah:

So, everything double checked, reassembled, and we're ready to start the engine. Bike fires into life and settles at a fast idle. ECU light is on but am guessing this is because starter was used to turn engine over with various sensors etc unplugged. Unfortunately, bike still has the same rattle, we spent a good couple of hours trying to track down the rattle with no success.
I also discovered my petrol tank seems to have grown about 5mm!!! It no longer fits in the frame, wtf?? Will finish putting back together this morning and take it over to a man who knows these bikes better than most to get his opinion....

 

Possiby discovered cause of rattle, the idle air pipe ends are all split, so she will be sucking air. Will get some on order and exhaust gaskets as another possibility and will balance tb's in the process.Hopefully that will cure it.

Also, have been looking at alternative front ends, with zrx1100 being a distinct possibility. If they do work out. should be able to retain the original triumph yolks. May still require some revalve/spring work but ultimately should be an instant improvement as is. Apparently, its fairly easy to extend the kwak forks internally by around 40mm so opens up a whole new avenue of potential front ends.