Maybe this info will help someone else thinking of racing an XR or Dominator:
Front End:
43mm ZZR1100 forks cost £30 on ebay (any 43mm superbike forks will fit the
XR yokes);
19" CB750 Comstar £35 on ebay, any 19" 2.15 or smaller will do;
Co-Built bespoke front spindle £60;
Bodywork:
1978 DT175 tank, £10 was pretty rusted and dented
Knight style fibreglass flat track tail unit (trimmed at the front to fit) £15
Modified seat pan, homemade £10
Airbox:
K&N air filter £30
I kept the airbox but removed the top and the sides and fitted mesh
panels. HRC recommended gauze #30 which is woven gauze 0.15mm~0.3mm wire
with 0.85mm spacing.
Rear Suspension:
I sent the original unit to MCT, who shortened it by 35mm, with a shorter and stiffer WP spring, they also revalved the unit so the compression and rebound adjustment is improved. (£220)
The budget option is a Talon lowering link (£30) and standard shock, but I found this was way too baggy and caused inconsistent grip.
Engine:
JE Pistons 102.5mm piston (654cc 10.5:1) and 103mm sleeve £350
Bored and honed by Hartlen Engineering £100
No head work yet, (I ran out of money), but Co-Built Anthony recommends an XRB cam from Kent Cams which has a longer duration profile and should make a huge difference after the big bore.
My bike is a 1987 twin carb 600R, and the rings were shagged, but if the donor is a later 650 you should be fine without any engine work if it's in decent condition
Rear Wheel Chain & Sprockets:
19" 2.15 SM Pro laced to the original XR hub by Central Wheel Components £220 (I would have preferred to use a later XR650 disk brake hub but was on a tight budget so still have a rear drum brake)
DID super heavy duty 520 chain £60 (113 links with the current gearing)
14/52 Talon sprockets (the rear will go up or down depending on the track)
Don't fit a 13 tooth front sproket as it causes the chain to chew up the sprocket retainer!
Budget option for standard rear - 17" Goldspeed supermoto wet or 18" dunlop K180 (depending on rim size)
Bars and Controls:
Venhill quick throtte (single cable) £60
Renthal MX bars £30
Pro Taper triple compound grips £6
Standard speedway cut-out £4
Tyres:
Maxxis DTR 7.0 CD3 (front) £120
Maxxis DTR 7.0 CD5 (rear) £120
Exhaust:
Projection Components oversized XR low-slung flat track 304 stainless tig welded headers (kinked out for maximum front tyre clearance to my spec). Now they have a jig and are offering them for sale at £350.
Budget ebay end can £50
Last year I raced with only the front end mods and a Talon lowering link with some part worn tyres, so only spent around £180 to get on the grid, but I'd definitely recommend sorting out the suspension if you're thinking about racing one of these, the original shock is way too baggy and caused me a few highsides!
The build is on my blog at Full Lock or Death
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DON'T FORGET - first race on the season is at Leicester, this Sunday, April 1. Racing from 11am till 9.30pm with a break from 5-7pm. I'm trying to find out if spectators get in free. I'll post on the blog when I find out.
2 comments:
hey jamie, the kudos on the bike!.
do the regs still say you have to fill the gaps in ur mag wheel?.
wouldnt want you to turn up on sun and find you could'nt ride.
my bros used to have three spoke wheels, had to put plastic covers over front...
I think it's a tenner for adults and kids are free.
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